Storing and Recalling Numbers
To store the number from the display into a data storage register: 1. Press ? (store). 2. Key in the register number: 0 through 9 for registers R0 through R9, or.0 through.9 for registers R.0 through R.9. Similarly, to recall a number from a storage register into the display, press : (recall), then key in the register number. This copies the number from the storage register into the display; the number remains unaltered in the storage register. Furthermore, when this is done, the number previously in the display is automatically held inside the calculator for a subsequent calculation, just as the number in the display is held when you key in another number.
Page: 27 of 275 Dimension: 14.8 cm x 21 cm
Example: Before you leave to call on a customer interested in your personal computer, you store the cost of the computer ($1,250) and also the cost of a printer ($500) in data storage registers. Later, the customer decides to buy six computers and one printer. You recall the cost of the computer, multiply by the quantity ordered, and then recall and add the cost of the printer to get the total invoice. Keystrokes 1250?0 500?2 ; Later that same day Keystrokes (RPN mode) ; ::2 + Display Display

1,250.00 500.00

Stores the cost of the computer in R0. Stores the cost of the printer in R2. Turns the calculator off.
500.00 1,250.00 7,500.00 500.00 8,000.00
Turns the calculator back on. Recalls the cost of the computer to the display. Multiplies the quantity ordered to get the cost of the computers. Recalls the cost of the printer to the display. Total invoice.
Keystrokes (ALG mode) ; :+:2
500.00 1,250.00 6. 500.00 8,000.00
Turns the calculator back on. Recalls the cost of the computer to the display. Multiplies by the quantity ordered to get the cost of the computers. Recalls the cost of the printer to the display. Total invoice.
Page: 28 of 275 Dimension: 14.8 cm x 21 cm
Clearing Storage Registers
To clear a single storage register that is, to replace the number in it with zero merely store zero into it. You need not clear a storage register before storing data into it; the storing operation automatically clears the register before the data is stored. To clear all storage registers at once including the financial registers, the stack registers, and the LAST X register press fCLEARH.* This also clears the display. All storage registers are also cleared when Continuous Memory is reset (as described on page 86).

Generalized Cash Flow Diagrams
Examples of various kinds of financial calculations, together with the applicable cash flow diagrams, appear under Compound Interest Calculations later in this section. If your particular problem does not match any of those shown, you can solve it nevertheless by first drawing a cash flow diagram, then keying the quantities identified in the diagram into the corresponding registers. Remember always to observe the sign convention when keying in PV, PMT, and FV. The terminology used for describing financial problems varies among the different segments of the business and financial communities. Nevertheless, most problems involving compound interest can be solved by drawing a cash flow diagram in one of the following basic forms. Listed below each form are some of the problems to which that diagram applies.
Page: 47 of 275 Dimension: 14.8 cm x 21 cm
Page: 48 of 275 Dimension: 14.8 cm x 21 cm
Compound Interest Calculations
Specifying the Number of Compounding Periods and the Periodic Interest Rate
Interest rates are usually quoted at the annual rate (also called the nominal rate): that is, the interest rate per year. However, in compound interest problems, the interest rate entered into i must always be expressed in terms of the basic compounding period, which may be years, months, days, or any other time unit. For example, if a problem involves 6% annual interest compounded quarterly for 5 years, n the number of quarters would be = 20 and i the interest rate per quarter would be 6% 4 = 1.5%. If the interest were instead compounded monthly, n would be = 60 and i would be 6% 12 = 0.5%. If you use the calculator to multiply the number of years by the number of compounding periods per year, pressing n then stores the result into n. The same is true for i. Values of n and i are calculated and stored like this in Example 2 on page 59. If interest is compounded monthly, you can use a shortcut provided on the calculator to calculate and store n and i: To calculate and store n, key the number of years into the display, then press gA. To calculate and store i, key the annual rate into the display, then press gC. Note that these keys not only multiply or divide the displayed number by 12; they also automatically store the result in the corresponding register, so you need not press the n or key next. The gA and gC keys are used in Example 1 on page 59.

144.25 25.83

Oops! You mistakenly keyed in the second number first. Exchanges the first and second numbers. The first number keyed in is now in the display. The answer is obtained by pressing the operation key.

118.42

Page: 90 of 275 Dimension: 14.8 cm x 21 cm
The ~ key is also useful for checking the first number entered to make sure you keyed it in correctly. Before pressing the operation key or equals key, however, you should press ~ again to return the second number entered to the display. Regardless of how many times you press ~, the calculator considers the number in the display to be the second number entered.
Occasionally you may want to recall to the display the number that was there before an operation was performed. (This is useful for doing arithmetic calculations with constants and for recovering from errors in keying in numbers.) To do so, press gF (LAST X). This section describes how to use gF in RPN mode.
Arithmetic Calculations With Constants
Example: At Permex Pipes a certain pipe fitting is packaged in quantities of 15, 75, and 250. If the cost per fitting is $4.38, calculate the cost of each package. Keystrokes (RPN mode) 15\ 4.gF Display
15.00 4.38 65.70 75. 4.38
Keys first quantity into calculator. Keys unit cost into display. Cost of a package of 15. Keys second quantity into display. Recalls unit cost which was last number in display before was pressed into display. Cost of a package of 75. Keys third quantity into display. Recalls unit cost into display again. Cost of a package of 250.

250 gF

328.50 250. 4.38 1,095.00
Another method for doing arithmetic calculations with constants is described on page 235.
Page: 91 of 275 Dimension: 14.8 cm x 21 cm
Recovering From Errors in Digit Entry
Example: Suppose you want to divide the total annual production for one of your firms products (429,000) by the number of retail outlets (987) in order to calculate the average number distributed by each outlet. Unfortunately, you mistakenly key in the number of outlets as 9987 rather than as 987. Its easy to correct: Keystrokes (RPN mode) 429000\ 9987 z gF Display
429,000.00 9,987. 42.96 9,987.00
You havent noticed your mistake yet. About 43 products per outlet but that seems too low! Recalls to the display the number that was there before you press z. You see that you keyed it in wrong. Begins the problem over. The correct answer.

0.258 3.88

Keys the number into the display. The reciprocal of 0.258, the original number.
Any of the above functions can be done with a number in the display resulting from a previous calculation, as well as with a number you have just keyed in. The examples below indicate how gF can recall the original number for further use in RPN mode. Keystrokes (RPN mode) fCLEARX Display

3875968992 3.88

Displays all 10 digits of the number inside the calculator. Display returns to normal format when X key is released. The number now in the display appears the same as before, but Displaying all 10 digits of the number inside the calculator shows fB has changed the number to match its displayed version. Display returns to normal format. The integer portion of the number previously displayed. Recalls the original number to the display in RPN mode only. The fractional portion of the number previously displayed.

fB fCLEARX

3.88 3880000000

g gF gT

3.00 3.88 0.88
Page: 101 of 275 Dimension: 14.8 cm x 21 cm
102 Section 7: Mathematics and Number-Alteration Functions
The Power Function in RPN Mode
Pressing q calculates a power of a number that is, yx. Like the arithmetic function +, q requires two numbers: 1. Key in the base number (which is designated by the y on the key). 2. Press \ to separate the second number (the exponent) from the first (the base). 3. Key in the exponent (which is designated by the x on the key). 4. Press q to calculate the power. To Calculate Keystrokes (RPN mode) 2\1.4q 2\1.4q 2\3q

21.4 21.4 (2)3

2.64 0.38 8.00 1.26

2 or 2

The Power Function in ALG Mode
To calculate a power of a number, that is, yx, in ALG mode, do the following: 1. Key in the base number (which is designated by the y on the key). 2. Press q and key in the exponent (which is designated by the x on the key) 3. Press } to calculate the power.

To Calculate

Keystrokes (ALG mode)

2q1.4} 2q1.4} 2q3}

Display 2.64 0.38 8.00 1.26
Page: 102 of 275 Dimension: 14.8 cm x 21 cm

Page: 149 of 275 Dimension: 14.8 cm x 21 cm
150 Section 11: Multiple Programs
Example 1: Assuming that program memory still contains the last program from the preceding section (which consisted of 17 program lines in RPN mode and 23 program lines in ALG mode), store after that program the office-supplies program from Section 8 (page 104). Since this is the second program to be stored in program memory, well ensure that a i000 instruction separates it from the first program by doing step 3 in the procedure above. Furthermore, since this program does not end with a loop, well do steps 5 and 6 too. Keystrokes (RPN mode) fs gi.017 gi000 \ b 5 + t gi019 fs Display Sets calculator to Program mode.
017,43, 33,002 018,43, 33,000 019, 020, 021, 022, 023, 024, 025, 026, 12,000.31
Sets calculator to last line keyed into program memory. Ensures that second program is separated from first by i000.

Keys in program.

Halts program execution. Branches to beginning of program. Sets calculator back to Run mode. (Display shown assumes results remain from running program in previous example.)

027,43, 33,019

Keystrokes (ALG mode) fs gi.023 gi000
023,43, 33,002 024,43, 33,000
Page: 150 of 275 Dimension: 14.8 cm x 21 cm
Section 11: Multiple Programs
Keystrokes (ALG mode) b + 5 } t gi025 fs
025, 026, 027, 028, 029, 030, 031, 032, 12,000.00
Halts program execution. Branches to beginning of program. Sets calculator back to Run mode. (Display shown assumes results remain from running program in previous example.) Keys in program.

033,43, 33,025

Example 2: With the two programs now stored in program memory from the preceding examples (occupying 27 program lines in RPN mode and 33 lines in ALG mode), store the amortization program from Section 9(page 125). Since there are already two programs stored in program memory, well skip step 3 in the procedure above. Furthermore, since the amortization program ends with a loop, well skip steps 5 and 6. When the amortization program was stored at the beginning of program memory, the i instruction at the end of the program branched to the :0 instruction in line 002. In the RPN program, since the :0 instruction is now in line 029, well specify that line number with the i instruction in line 034. In the ALG program, since the :0 instruction is now in line 035, well specify that line number with the i instruction in line 041. Keystrokes (RPN mode) fs gi.027 Display Sets calculator to Program mode.
027,43, 33,019 Sets calculator to last line
keyed into program memory.
Page: 151 of 275 Dimension: 14.8 cm x 21 cm
152 Section 11: Multiple Programs
Keystrokes (RPN mode) ?0 :0 f! gu ~ gu gi029
028, 029, 030, 031, 032, 033,

Keys in program

034,43, 33,029

KEYSTROKES (RPN mode)

fCLEAR M M* ?.1 :n ?0 :$ fCLEARG :1 $ :2 gA :3 gC P 0 n :2
DISPLAY 000, 001, 002, 003, 004,005, 006, 007, 008, 009, 010, 011, 012, 013, 014, 015, 016, 017, 018, 019, 020, 021, 2

KEYSTROKES (ALG mode)

fCLEAR M M* ?.1 :n ?0 :$ fCLEARG :1 $ :2 gA :3 gC P 0 n :0 1
DISPLAY 000, 001, 002, 003, 004,005, 006, 007, 008, 009, 010, 011, 012, 013, 014, 015, 016, 017, 018, 019, 020, 021, 1
* FV is repeated in the program twice to ensure that it is computed and not stored.
Page: 164 of 275 Dimension: 14.8 cm x 21 cm
f! :n z :4 + :.0 b :4 :5 :8 + :P + P :.1 :7 b :$ -
DISPLAY 022, 023, 024, 025, 026, 027, 028, 029,030, 031, 032, 033, 034, 035, 036, 037, 038, 039, 040,041, 042, 043, 044, 045, 30
2 f! z :n + :4 :.0 b :4 :5 + :8 + :P P :.1 :7 b -
DISPLAY 022, 023, 024, 025, 026, 027, 028, 029, 030,031, 032, 033, 034, 035, 036, 037, 038, 039, 040, 041,042, 043, 044, 045, 25 30
Page: 165 of 275 Dimension: 14.8 cm x 21 cm
166 Section 12: Real Estate and Lending
M t :1 :6 + $ :gC t :9 gC M fs
DISPLAY 046, 047, 048, 049, 050, 051, 052, 053, 054,45, 43 055, 056, 057, 058, 15
:$ M t :1 :6 $ :gC t :9 gC M fs
DISPLAY 046, 047, 048, 049, 050, 051, 052, 053, 054, 055,45, 43 056, 057, 058, 059, 15

REGISTERS

n: Period FV: Used R3: i(Mtg) R7: % Comm. R.1: Market V. i: Apprec. R0: Period R4: Taxes/Mo R8: Rent PV: Price R1: Dwn Pmt R5: Improve./mo R9: Savings i PMT: Used R2: Life R6: Closing C. R.0: Tax Bracket
Page: 166 of 275 Dimension: 14.8 cm x 21 cm
1. Key in the program. 2. Key in the estimated down payment then press ?1. 3. Key in the life of the mortgage then press ?2. 4. Key in the annual mortgage interest rate then press ?3. 5. Key in the estimated monthly taxes then press ?4. 6. Key in the total amount estimated for monthly repairs, improvements, incremental insurance, utility costs, and other expenses, then press ?5. 7. Key in the closing costs then press ?6. 8. Key in the selling cost as a percentage of the selling price. This should include sales commission, escrow fees, etc. then press ?7. 9. Key in the monthly rent for the alternative housing then press ?8. 10. Key in the savings or alternative investment annual interest rate as a percentage then press ?9. 11. Key in the combined State and Federal marginal tax rate* as a percentage then press ?.0. 12. Press g and fCLEARG then key in the number of years involved in the investment; press n. 13. Key in the estimated rate of yearly appreciation as a percentage then press. 14. Key in the price of the house under consideration then press $. 15. Press t to compute the net proceeds from the sale of the house. (A negative value indicates money lost.) 16. Press t to compute the yield on your investment in the house. 17. Press t to compute the value of a savings account or other investment. 18. Compare the value of the hypothetical savings account to the net proceeds of the sale of the house. Examine the sign and magnitude of the yield to arrive at your decision. 19. To change data and repeat the calculations, store the changed values in the appropriate registers and go to step 12.

fs fCLEAR z ?1 ~ ??f :1 ?3 :$ ~ -
000, 001, 002, 003, 004, 005, 006, 007, 008, 009, 010, 011, 012, 013, 014, 015, 016, 017, 34 30

fCLEAR z ?1 ~ ??f :1 ?3

000, 001, 002, 003, 004, 005, 006, 007, 008, 009, 010, 011, 012, 013, 014, 015, 016, 017, 3
Page: 180 of 275 Dimension: 14.8 cm x 21 cm
$ :n :1 n :0 gm gi035 :2 gu :0 f t 1 ?=0 ?=2 gi026 :2 gu :$ :M :3 gi030
DISPLAY 018, 019, 020, 021, 022, 023, 024, 35
:$ ~ $ :n :1 n :0 gm gi038 :2 gu :0 f t 1 ?=0 ?=2 gi029 :2 gu :$ -
DISPLAY 018, 019, 020, 021, 022, 023, 024, 025, 026, 027, 35
025,43,33, 035 026, 027, 028, 029, 030, 031, 032,033,0 2
028,43,33, 038 029, 030, 031, 032, 033, 034, 035,036,0 2
034,43,33, 026 035, 036, 037, 038, 039, 040, 3
037,43,33, 029 038, 039, 040, 041, 30
Page: 181 of 275 Dimension: 14.8 cm x 21 cm
182 Section 13: Investment Analysis

:M :3 gi033 fs

DISPLAY 042, 043, 044, 3
Page: 182 of 275 Dimension: 14.8 cm x 21 cm
RPN Mode: 6. Key in the year desired then press \. 7. Key in the number of months in first year* then press t. The display will show the amount of depreciation for the desired year. If desired, press ~ to see the remaining depreciable value, then press :$:3=~-:M- to find the total depreciation through the current year. ALG Mode: 6. Key in the year desired then press. 7. Key in the number of months in first year* then press t. The display will show the amount of depreciation for the desired year. If desired, press ~ to see the remaining depreciable value, then press :$=:3-~-:M to find the total depreciation through the current year. 8. Press t for the amount of depreciation then, if desired, press ~ for the remaining depreciable value for the next year. Repeat this step for the following years. 9. For a new case press gi000 and return to step 2. Example: A commercial movie camera is purchased for $12,000. If maintained properly, the camera has a useful life expectancy of 25 years with $500 salvage value. Using the sum-of-the-years-digits method, what is the amount of depreciation and the remaining depreciable value for the 4th and 5th years? Assume the first depreciation year is 11 months long. Keystrokes (RPN mode) f] fCLEARG 12000$ 500M 25n 4\ Keystrokes (ALG mode) f[ fCLEARG 12000$ 500M 25n 4 Display
12,000.00 500.00 25.00 4.00
Book value. Salvage value. Life. Year desired.
Page: 183 of 275 Dimension: 14.8 cm x 21 cm
184 Section 13: Investment Analysis
Keystrokes (RPN mode) 11t ~ t ~
Keystrokes (ALG mode) 11t ~ t ~
4.00 781.41 8,238.71 5.00 746.02 7,492.69
Fourth year: depreciation, remaining depreciable value. Fifth year: depreciation, remaining depreciable value.
Full- and Partial-Year Depreciation with Crossover
When calculating declining-balance depreciation it is often advantageous for tax purposes to switch from declining balance to straight-line depreciation at some point. This hp 12c platinum program calculates the optimum crossover point and automatically switches to straight-line depreciation at the appropriate time. The crossover point is the end of the year in which the declining-balance depreciation last exceeds or equals the amount of straight-line depreciation. The straight-line depreciation is determined by dividing the remaining depreciable value by the remaining useful life. Given the desired year and the number of months in the first year, this program calculates the depreciation for the desired year, the remaining depreciable value, and the total depreciation through the current year.

fs fCLEAR z ?6 :n ~ -

000, 001, 002, 003, 004, 005, 006, 007, 30

fCLEAR z ?6 :n -

Page: 184 of 275 Dimension: 14.8 cm x 21 cm
?4 d ??-0 ?2 ?3 f# :6 ?1 :$ ~ $ \ gF ~ :M ~ :go
DISPLAY 008, 009, 010, 011, 012,013, 014, 015, 016, 017, 018, 019, 020, 021, 022, 023, 024, 025, 026, 027, 028, 029, 030, 031, 1 34
~ ?4 d d ??-0 ?2 ?3 f# :6 ?1 :$ ~ $ :1 :$ :M
DISPLAY 008, 009, 010, 011, 012, 013, 014, 015,016, 017, 018, 019, 020, 021, 022, 023, 024, 025, 026, 027, 028, 029, 030, 031, 36
Page: 185 of 275 Dimension: 14.8 cm x 21 cm
186 Section 13: Investment Analysis
gi039 d d 1 gu d t 1 ?+2 ?-0 f# ?+1 ?5 :$ :M :4 z go gi053 gi065 d 0 :0
DISPLAY 032,43,33, 039 033, 034, 035, 036, 037, 038, 039, 040,041,042, 43 34
~ :go gi043 d d 1 gu d t 1 ?+2 ?-0 f# ?+1 ?5 :$ :M z :4 go
DISPLAY 032, 033, 034, 035, 1 34
036,43,33, 043 037, 038, 039, 040, 041, 042, 043, 044,045,046, 43 34
043,044, 045, 046, 047, 048, 049, 050, 45
047,048, 049, 050, 051, 052, 053, 054, 055, 44 45
051,43,33, 053 052,43,33, 065 053, 054, 055, 0 0
Page: 186 of 275 Dimension: 14.8 cm x 21 cm
go gi086 :$ :5 $ 1 ?-4 gi040 :4 n 0 ??-2 ?=0 :5 ?-1 :3 fV ?+?-0 ?+2

DISPLAY 056, 43 34

gi058 gi070 d 0 :0 go gi091 :$ :5 $ 1 ?-4 gi044 :4 n 0 ??-2 ?=0 :5 ?-1 :3
DISPLAY 056,43,33, 058 057,43,33, 070 058, 059, 060, 061, 0 34
057,43,33, 086 058, 059, 060, 061, 062, 063,1 4
062,43,33, 091 063, 064, 065, 066, 067, 068,1 4
064,43,33, 040 065, 066, 067, 068, 069, 070,071,072, 0 2
069,43,33, 044 070, 071, 072, 073, 074, 075,076,077, 3

073,074, 075, 45 42

076,077, 078,079,44 40

078,079, 45

Page: 187 of 275 Dimension: 14.8 cm x 21 cm
188 Section 13: Investment Analysis
?+3 d :go gi074 d d :2 gu d t :6 gm gi074 gi058 fs
DISPLAY 080,081, 082, 083, 084, 34
fV ?+?-0 ?+2 ?+3 d :go gi079 d d :2 gu d t :6 gm gi079 gi063 fs

DISPLAY 080, 34

081,082, 083,084,085,086, 087, 088, 089,
085,43,33, 074 086, 087, 088, 089, 090, 091, 092, 093, 6 35
090,43,33, 079 091, 092, 093, 094, 095, 096, 097, 098, 6 35
094,43,33, 074 095,43,33, 058
099,43,33, 079 100,43,33, 063
Page: 188 of 275 Dimension: 14.8 cm x 21 cm
n: Life FV: Salvage R3: Used i: Factor R0: Used R4: Used PV: Dep. Value R1: Dep. R5: Used PMT: Unused R2: Counter R6: Used
1. Key in the program. 2. Press fCLEARH. 3. Key in the book value then press $. 4. Key in the salvage value then press M. 5. Key in the life in years (an integer) then press n. 6. Key in the declining-balance factor as a percentage then press. 7. RPN: Key in the desired year and press \. 7. ALG: Key in the desired year and press. 8. Key in the number of months in the first year* then press t to calculate the amount of depreciation for the desired year. 9. If desired, press ~ to see the remaining depreciable value. 10. If desired, press :1 to see the total depreciation through the current year. 11. Continue pressing t* to find the amount of depreciation for the successive years. Steps 9 and 10 may be repeated for each year. 12. For a new case press gi000 and return to step 2. Example: An electronic instrument is purchased for $11,000, with 6 months remaining in the current fiscal year. The instruments useful life is 8 years and the salvage value is expected to be $500. Using a 200% declining-balance factor, generate a depreciation schedule for the instruments complete life. What is the remaining depreciable value after the first year? What is the total depreciation after the 7th year? Keystrokes (RPN mode) f] fCLEARH 11000$ Keystrokes (ALG mode) f[ fCLEARH 11000$ Display

0.00 11,000.00

Book value.
* Refer to straight-line depreciation note page 174. The display will pause with the year number before displaying the amount of depreciation for

that year.

Page: 189 of 275 Dimension: 14.8 cm x 21 cm
190 Section 13: Investment Analysis
Keystrokes (RPN mode) 500M 8n 200 1\ 6t ~
Keystrokes (ALG mode) 500M 8n 6t ~
500.00 8.00 200.00 1.00 1.00 1,375.00 9,125.00 2.00 2,406.25 3.00 1,804.69 4.00 1,353.51 5.00 1,015.14 6.00 761.35 7.00 713.62 9,429.56 8.00 713.63 9.00 356.81
Salvage value. Life. Declining-balance factor. First year depreciation desired. First year: depreciation, remaining depreciable value. Second year: depreciation. Third year: depreciation. Fourth year: depreciation. Fifth year: depreciation. Sixth year: depreciation.* Seventh year: depreciation. Total depreciation through the seventh year. Eight year: depreciation Ninth year: depreciation.

t t t t t t :1 t t

* By observation the crossover was year 6. Years 7, 8, and 9 use straight-line depreciation.
Page: 190 of 275 Dimension: 14.8 cm x 21 cm

Excess Depreciation

When accelerated depreciation is used, the difference between total depreciation charged over a given period of time and the total amount that would have been charged under straight-line depreciation is called excess depreciation. To obtain excess depreciation: RPN Mode: 1. Calculate the total depreciation then press \. 2. Key in the depreciable amount (cost less salvage) then press \. Key in the useful life of the asset in years then press z. Key in the number of years in the income projection period then press to get the total straight-line depreciation charge. 3. Press - to get the excess depreciation. ALG Mode: 1. Calculate the total depreciation then press -g. 2. Key in the depreciable amount (cost less salvage) then press z. Key in the useful life of the asset in years then press. Key in the number of years in the income projection period then press g to get the total straight-line depreciation charge. 3. Press to get the excess depreciation. Example: What is the excess depreciation in the previous example over 7 calendar years? (Because of the partial first year, there are 6.5 years depreciation in the first 7 calendar years.) Keystrokes (RPN mode) 9429.56\ 10500\ 8z 6.5 Keystrokes (ALG mode) Display Total depreciation through seventh year. Depreciable amount. Yearly straight-line depreciation. Total straight-line depreciation. Excess depreciation

12.00 9.00 0.83 1.00 11.64 64.45
Duration of lease. Number of periodic payments.
Monthly payment to be received.
If solving for the payment amount will be done repetitively, key in the following hp 12c platinum program. KEYSTROKES (RPN mode) fs fCLEAR g fCLEARG :0 :1 n :2 DISPLAY KEYSTROKES (ALG mode) fs DISPLAY
000, 001, 002, 003, 004, 005, 006, 007, 11 2
fCLEAR g fCLEARG :0 :1 n :2
Page: 203 of 275 Dimension: 14.8 cm x 21 cm

204 Section 14: Leasing

KEYSTROKES (RPN mode) 1 P $ :1 + :3 ~ z fs
008, 009, 010, 011, 012, 013, 014, 015, 016, 017, 45 45

1 P $ + :1 :3 z ~ fs

008, 009, 010, 011, 012, 013, 014, 015, 016, 017, 018, 019, 45 45
n: n#Adv. Pmt. FV: 0 R3: Loan i: i R0: n R4R.7: Unused PV: Used R1: #Adv. Pmt. PMT: 1 R2: i
1. Key in the program. 2. Key in the total number of payments in the lease then press ?0. 3. Key in the total number of payments made in advance then press ?1. 4. Key in the periodic interest rate as a percentage then press ?2. 5. Key in the loan amount and press ?3; then press t to obtain the periodic payment to be received by the lessor. 6. For a new case, return to step 2. The values changed from the previous case are the only values which need to be entered.
Page: 204 of 275 Dimension: 14.8 cm x 21 cm
Example 2: Using the preceding program, solve for the monthly payment using the information given in example 1. Then change the yearly interest to 15% and solve for the new payment amount. Keystrokes (RPN mode) f] 12?0 3?1 10\12z ?2 750?3t 15\12z ?2t Keystrokes (ALG mode) f[ 12?0 3?1 10z12 ?2 750?3t 15z12 ?2t Display
12.00 3.00 0.83 0.83 64.45 1.25 65.43
Duration of lease. Number of advance payments.
Periodic interest rate. Monthly payment to be received.
Monthly payment to achieve a 15% yield.
Example 3: Using the information from example 1, what monthly payment is necessary to yield the lessor 15% annually if one payment is due at the time of closing? Assuming that the previous example was just solved, the keystrokes are as follows: Keystrokes (RPN mode) 1?1t Keystrokes (ALG mode) 1?1t Display

The History Stack in ALG Mode
In ALG mode, the stack holds a history of 4 completed results. These results may be rearranged using d and ~ in the same way as described on page 230, for RPN mode. Note that once a two-numbered function (such as +, -, , z or q) has had the second argument entered, the two arguments cannot then be swapped using ~ because when the second argument is entered it replaces the first, which is removed from the stack. So, if you wish to do 25.83 - 144.25, but then realize you meant to do 144.25 - 25.83, the way to correct this is to proceed and do }. All ~ will do at this point is replace the 144.25 with whatever was displayed before the 25.83 was entered, and the first argument remains unchanged.
Page: 239 of 275 Dimension: 14.8 cm x 21 cm
240 Appendix B: Algebraic Mode (ALG)
The stack diagrams showing the output for the Calendar and Financial functions on page 233 are the same for ALG as RPN mode. To add INT and PRICE after executing the bond E function, press +~}. In this case, ~ is used to enter the second argument for the + operation. After executing +~}, the total price (INT + PRICE) will be displayed. LAST X will be unchanged, but the original PRICE will be found in the Y-register. One can also do +d} to get the total price, with the only difference being that the original PRICE would then be in the T-register.
In ALG mode, parentheses can be used in calculations to change the order in which operations are evaluated. When there are pending open parentheses, the ( ) status indicator will be shown in the display. As open parentheses are closed, the expression contained within the parentheses is evaluated. The final result of a calculation will be displayed when you press the key, and then any pending parentheses will be closed. You cant use more than 13 pending (opened) parentheses at the same time.
Keying 1 will calculate first and then the result (1.6) will have 1 subtracted from it (resulting in 0.6). Keystrokes (ALG mode) OO 8zg51g Display
Page: 240 of 275 Dimension: 14.8 cm x 21 cm
In most cases, b divides a number by 100. The one exception is when a plus or minus sign precedes the number. For instance, 25 b results in 0.25. To find 25% of 200, press: b}. (Result is 50.) You can also calculate a net amount all in one calculation: For instance, to decrease 200 by 25%, just enter 200-25b}. (Result is 150.) Example: You borrow $1,250 from a relative, and agree to repay the loan in a year with 7% simple interest. How much money will you owe? Keystrokes (ALG mode) OO 1250+7b } Display

Mortgages

The amount of the repayments on home loans and mortgages offered by banks in the United Kingdom can usually be calculated as described under Calculating the Payment Amount, page 58. Building Societies in the United Kingdom, however, calculate the amount of these repayments differently. In general, the repayment amount of a Building Society mortgage is calculated as follows: first, the annual repayment amount is calculated using the annual interest rate; second, the periodic repayment amount is calculated by dividing the annual repayment amount by the number of repayment periods in one year. Furthermore, the calculations used by Building Societies are rounded; therefore, to match their scale repayment figures you would have to round your calculations accordingly.
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268 Appendix G: United Kingdom Calculations
Annual Percentage Rate (APR) Calculations
In the United Kingdom, the calculation of the Annual Percentage Rate of Charge (APR) in accordance with the United Kingdom Consumer Credit Act (1974) differs from the calculation of the APR in the United States. Unlike the practice in the United States, where the APR can be calculated by multiplying the periodic interest rate by the number of periods per year, in the United Kingdom the APR is calculated by converting the periodic interest rate to the effective annual rate, then rounding the result to one decimal place. With the periodic interest rate in the display and in the i register and the payment mode set to End, the effective annual rate can be calculated by pressing P, then keying in the number of compounding periods per year and pressing w0$M. Pressing f1 will then display the rounded APR.
Solutions for the price and yield to maturity of United Kingdom bonds are not included in this handbook. Actual practice differs according to the type of bond; variations such as cumulative and ex-dividend pricing, simple or compound interest discounting, etc., may be encountered. Application Notes covering such situations may be available in the United Kingdom; check with your local authorized Hewlett-Packard dealer.

Page: 268 of 275 Dimension: 14.8 cm x 21 cm

Function Key Index

General ; Power on /off key (page 16). f Shift key. Selects alternate function in gold above the function keys (page 16). Also used in display formatting (page 87). g Shift key. Selects alternate function in blue on the slanted face of the function keys (page 16). fCLEARX after f, g, ?, : or i, cancels that key (page 19). fCLEARX also displays mantissa of number in the displayed X-register (page 89). Backspacing. Deletes last character or a number. (page 18). Undo. Recovers the last operation. (page 19). Digit Entry \ Enters a copy of number in displayed X-register into Y-register. Used to separate numbers (pages 21 and 229). Changes sign of number or exponent of 10 in X-register (page 17). Enter exponent. After pressing, next numbers keyed in are exponents of 10 (page 18). digits. Used for keying in numbers (page 21) and display formatting (page 87). Decimal point (page 17). Also used for display formatting (page 87). O Clears contents of displayed X-register to zero (page 19). Arithmetic +-z} Arithm etic operators (page 21). Storage Registers ? Store. Followed by number key, decimal point and number key, or top row financial key, stores displayed number in storage register specified (page 27). Also used to perform storage register arithmetic (page 29). : Recall. Followed by number key, decimal point and number key, or top-row financial key, recalls value from storage register specified into the displayed X-register (page 27). CLEAR H Clears contents of stack (X,Y,Z and T), all storage registers, statistical registers, and financial registers (page 28). Leaves program memory untouched; not programmable. Percentage b Computes x% of y and retains the y-value in the Y-register (page 31). Computes percent of change between number in Y-register and number in displayed X-register (page 33). Z Computes percent that x is of number in Y-register (page 35). Calendar Sets date format to day-month-year (page 38); not programmable. Sets date format to month-day-year (page 37); not programmable. D Changes a date in the Y-register by the number of days in the X-register and displays day of week (page 38). Computes the number of days between two dates in the Y and X-registers (page 40).
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270 Function Key Index

Financial CLEAR G Clears contents of financial registers (page 42). Sets payment mode to Begin for compound interest calculations involving payments (page 46). Sets payment mode to End for compound interest calculations involving payments (page 46). Calculates simple interest (page 42). w Stores or computes number of periods in financial problem (page 41). A Multiplies a number in displayed X-register by 12 and stores the resulting value in the n-register (page 49). Stores or computes interest rate per compounding period (page 41). C Divides number in displayed X-register by 12 and stores the resulting value in the i-register (page 49). $ Stores or computes the present value (that is, the initial cash flow) of a financial problem (page 41). P Stores or computes payment amount (page 41).

File name: hp 12c_user's guide_English_HDPMBF12E44 Printed Date: 2005/7/29
Page: 3 of 209 Dimension: 14.8 cm x 21 cm
The various appendices describe additional details of calculator operation as well as warranty and service information. The Function Key Index and Programming Key Index at the back of the handbook can be used as a handy page reference to the comprehensive information inside the manual
Financial Calculations in the United Kingdom
The calculations for most financial problems in the United Kingdom are identical to the calculations for those problems in the United States which are described in this handbook. Certain problems, however, require different calculation methods in the United Kingdom than in the United States. Refer to Appendix F for more information.
For More Solutions to Financial Problems
In addition to the specialized solutions found in Sections 12 through 16 of this handbook, many more are available in the optional hp 12c Solutions Handbook. Included are solutions to problems in lending, forecasting, pricing, statistics, savings, investment analysis, personal finance, securities, Canadian mortgages, learning curves in manufacturing, and queuing theory. A Solutions Handbook is available online (www.hp.com/calculators).
Page: 4 of 209 Dimension: 14.8 cm x 21 cm

Contents

Introduction... 3
About This Handbook...3 Financial Calculations in the United Kingdom..4 For More Solutions to Financial Problems..4

Part I.

Problem Solving... 15
Section 1: Getting Started.. 16
Power On and Off..16 Low-Power Indication..16 The Keyboard...16 Keying in Numbers...17 Digit Separators...17 Negative Numbers...17 Keying in Large Numbers..18 The CLEAR Keys...18 Simple Arithmetic Calculations..19 Chain Calculations...20 Storage Registers...23 Storing and Recalling Numbers..23 Clearing Storage Registers..24 Storage Register Arithmetic...24
Section 2: Percentage and Calendar Functions. 26
Percentage Functions...26 Percentages...26 Net Amount...27 Percent Difference...27 Percent of Total...28 Calendar Functions...29 Date Format...29 Future or Past Dates...30 Number of Days Between Dates...31
Section 3: Basic Financial Functions. 32
The Financial Registers...32 Storing Numbers Into the Financial Registers..32 Displaying Numbers in the Financial Registers..32 5
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Clearing the Financial Registers... 33 Simple Interest Calculations... 33 Financial Calculations and the Cash Flow Diagram. 34 The Cash Flow Sign Convention... 36 The Payment Mode... 37 Generalized Cash Flow Diagrams.. 37 Compound Interest Calculations... 39 Specifying the Number of Compounding Periods and the Periodic Interest Rate... 39 Calculating the Number of Payments or Compounding Periods. 39 Calculating the Periodic and Annual Interest Rates. 43 Calculating the Present Value.. 44 Calculating the Payment Amount.. 46 Calculating the Future Value... 48 Odd-Period Calculations... 50 Amortization... 54

Section 4: Additional Financial Functions.. 57
Discounted Cash Flow Analysis: NPV and IRR.. 57 Calculating Net Present Value (NPV).. 58 Calculating Internal Rate of Return (IRR).. 63 Reviewing Cash Flow Entries... 64 Changing Cash Flow Entries... 65 Bond Calculations... 66 Bond Price...67 Bond Yield...67 Depreciation Calculations... 68
Section 5: Additional Operating Features.. 70
Continuous Memory... 70 The Display... 71 Status Indicators.. 71 Number Display Formats.. 71 Scientific Notation Display Format.. 72 Special Displays.. 73 The key...74 The Key...74 Arithmetic Calculations With Constants. 75 Recovering From Errors in Digit Entry.. 75
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Section 6: Statistics Functions.. 76
Accumulating Statistics... 76 Correcting Accumulated Statistics...77 Mean....77 Standard Deviation...79 Linear Estimation...80 Weighted Mean...81
Section 7: Mathematics and Number-Alteration Functions 83
One-Number Functions...83 The Power Function...85
Part II. Programming.. 87 Section 8: Programming Basics.. 88
Why Use Programs?...88 Creating a Program...88 Running a Program...89 Program Memory...90 Identifying Instructions in Program Lines.91 Displaying Program Lines...92 The 00 Instruction and Program Line 00..93 Expanding Program Memory..94 Setting the Calculator to a Particular Program Line.95 Executing a Program One Line at a Time...96 Interrupting Program Execution..97 Pausing During Program Execution..97 Stopping Program Execution..101
Section 9: Branching and Looping. 103
Simple Branching...103 Looping...104 Conditional Branching...107
Section 10: Program Editing... 113
Changing the Instruction in a Program Line.113 Adding Instructions at the End of a Program..114 Adding Instructions Within a Program..115 Adding Instructions by Replacement..115 Adding Instructions by Branching..116
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Section 11: Multiple Programs.. 120
Storing Another Program.. 120 Running Another Program... 122
Part III. Solutions.. 123 Section 12: Real Estate and Lending.. 124
Annual Percentage Rate Calculations With Fees.. 124 Price of a Mortgage Traded at a Discount or Premium.. 126 Yield of a Mortgage Traded at a Discount or Premium. 128 The Rent or Buy Decision.. 130 Deferred Annuities... 134
Section 13: Investment Analysis. 136
Partial-Year Depreciation... 136 Straight-Line Depreciation... 136 Declining-Balance Depreciation.. 139 Sum-of-the-Years-Digits Depreciation.. 141 Full- and Partial-Year Depreciation with Crossover. 144 Excess Depreciation.. 148 Modified Internal Rate of Return... 148

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Note: A battery symbol ( ) shown in the lower-left corner of the display when the calculator is on signifies that the available battery power is nearly exhausted. To install new batteries, refer to Appendix E. The calendar functions and nearly all of the financial functions take some time to produce an answer. (This is typically just a few seconds, but the , !, L, and S functions could require a half-minute or more.) During these calculations, the word running flashes in the display to let you know that the calculator is running. Keystrokes fCLEARHf2
Display Clears previous data inside the calculator and sets display to show two decimal places. Calculates and stores the number of compounding periods. Calculates and stores the periodic interest rate. Stores periodic payment amount. Sets payment mode to Begin. Amount required to be deposited.*

4gA 6gC 500P g $

48.00 0.50 500.00 500.00 -21,396.61
Example 2: We now need to determine how to accumulate the required deposit by the time your daughter enters college 14 years from now. Lets say that she has a paid-up $5,000 insurance policy that pays 5.35% annually, compounded semiannually. How much would it be worth by the time she enters college? In this example, we need to calculate FV, the future value. Keystrokes fCLEARG 14\2n 5.35\2z 5000$ M Display
-21,396.61 28.00 2.68 -5,000.00 10,470.85
Clears previous financial data inside the calculator. Calculates and stores the number of compounding periods. Calculates and stores the periodic interest rate. Stores the present value of the policy. Value of policy in 14 years.

* Dont

be concerned now about the minus sign in the display. That and other details will be

explained in Section 3.

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Example 3: The preceding example showed that the insurance policy will provide about half the required amount. An additional amount must be set aside to provide the balance (21,396.61 10,470.85 = 10,925.76). Suppose you make monthly payments, beginning at the end of next month, into an account that pays 6% annually, compounded monthly. What payment amount would be required in order to accumulate $10,925.75 in the 14 years remaining? Keystrokes fCLEARG 14gA 6gC 10925.76M g P Display
10,470.85 168.00 0.50 10.925.76 10.925.76 41.65
Clears previous financial data inside the calculator. Calculates and stores the number of compounding periods. Calculates and stores the periodic interest rate. Stores the future value required. Sets payment mode to End. Monthly payment required.
Example 4: Suppose you cannot find a bank that currently offers an account with 6% annual interest compounded monthly, but you can afford to make $45.00 monthly payments. What is the minimum interest rate that will enable you to accumulate the required amount? In this problem, we do not need to clear the previous financial data inside the calculator, since most of it is unchanged from the preceding example. Keystrokes 45P 12 Display

45.00 0.42 5.01

Stores payment amount. Periodic interest rate. Annual interest rate.
This is only a small sampling of the many financial calculations that can now be done easily with your hp 12c. To begin learning about this powerful financial tool, just turn the page.
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Part I Problem Solving

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Section 1

Getting Started

Power On and Off

To begin using your hp 12c, press the ; key*. Pressing ; again turns the calculator off. If not manually turned off, the calculator will turn off automatically 8 to 17 minutes after it was last used.

Low-Power Indication

A battery symbol ( ) shown in the upper-left corner of the display when the calculator is on signifies that the available battery power is nearly exhausted. To replace the batteries, refer to Appendix E.

The Keyboard

Many keys on the hp 12c perform two or even three functions. The primary function of a key is indicated by the characters printed in white on the upper face of the key. The alternate function(s) of a key are indicated by the characters printed in gold above the key and the characters printed in blue on the lower face of the key. These alternate functions are specified by pressing the appropriate prefix key before the function key: To specify the alternate function printed in gold above a key, press the gold prefix key (f), then press the function key. To specify the primary function printed on the upper face of a key, press the key alone. To specify the alternate function printed in blue on the lower face of a key, press the blue prefix key (g), then press the function key.

* Note

that the ; key is lower than the other keys to help prevent its being pressed

inadvertently.

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Section 1: Getting Started
Throughout this handbook, references to the operation of an alternate function appear as only the function name in a box (for example, The L function ). References to the selection of an alternate function appear preceded by the appropriate prefix key (for example, Pressing fL ). References to the functions shown on the keyboard in gold under the bracket labeled CLEAR appear throughout this handbook preceded by the word CLEAR (for example, The CLEARH function or Pressing fCLEARH ). If you press the f or g prefix key mistakenly, you can cancel it by pressing fCLEARX. This can also be pressed to cancel the ?, :, and i keys. (These keys are prefix keys in the sense that other keys must be pressed after them in order to execute the corresponding function.) Since the X key is also used to display the mantissa (all 10 digits) of a displayed number, the mantissa of the number in the display will appear for a moment after the X key is released. Pressing the f or g prefix key turns on the corresponding status indicator f or g in the display. Each indicator turns off when you press a function key (executing an alternate function of that key), another prefix key, or fCLEARX.

the right time, if youre interested you can read all about it in Appendix A. By gaining a more complete understanding of the calculators operation, youll use it more efficiently and confidently, yielding a better return on the investment in your hp 12c.
Page: 22 of 209 Dimension: 14.8 cm x 21 cm

Storage Registers

Numbers (data) in the hp 12c are stored in memories called storage registers or simply registers. (The singular term memory is sometimes used in this handbook to refer to the entire collection of storage registers.) Four special registers are used for storing numbers during calculations (these stack registers are described in Appendix A), and another (called the LAST X register) is used for storing the number last in the display before an operation is performed. In addition to these registers into which numbers are stored automatically, up to 20 data storage registers are available for manual storage of numbers. These data storage registers are designated R0 through R9 and R.0 through R.9. Fewer registers are available for data storage if a program has been stored in the calculator (since the program is stored in some of those 20 registers), but a minimum of 7 registers is always available. Still other storage registers referred to as the financial registers are reserved for numbers used in financial calculations.
Storing and Recalling Numbers
To store the number from the display into a data storage register: 1. Press ? (store). 2. Key in the register number: 0 through 9 for registers R0 through R9, or.0 through.9 for registers R.0 through R.9. Similarly, to recall a number from a storage register into the display, press : (recall), then key in the register number. This copies the number from the storage register into the display; the number remains unaltered in the storage register. Furthermore, when this is done, the number previously in the display is automatically held inside the calculator for a subsequent calculation, just as the number in the display is held when you key in another number. Example: Before you leave to call on a customer interested in your personal computer, you store the cost of the computer ($3,250) and also the cost of a printer ($2,500) in data storage registers. Later, the customer decides to buy six computers and one printer. You recall the cost of the computer, multiply by the quantity ordered, and then recall and add the cost of the printer to get the total invoice. Keystrokes 3250?1 2500?2 ; Display

3,250.00 2,500.00

Stores the cost of the computer in R1. Stores the cost of the printer in R2. Turns the calculator off.
Page: 23 of 209 Dimension: 14.8 cm x 21 cm
Later that same day Keystrokes ; ::2 + Display

2,500.00 3,250.00

Turns the calculator back on. Recalls the cost of the computer to the display. the cost of the computers.

Instead of having a fractional (or balloon) payment at the end of the loan, you might wish to make 327 or 328 equal payments. Refer to Calculating the Payment Amount on page 46 for a complete description of this procedure.
* You could skip this step, since 328 is already stored in the n register. If you do so, however,
you will need to press M twice in the next step (for the reason discussed in the first footnote on page 32; you would not have to press M twice if you had not pressed 12z after w in the example above.) We choose to show this and the following example in a parallel format so that the procedure is easy to remember: the number you key is the number of the final payment either the fractional payment or the balloon payment whose amount is to be calculated.
Page: 41 of 209 Dimension: 14.8 cm x 21 cm
Example 2: Youre opening a savings account today (the middle of the month) with a $775 deposit. The account pays 61/4% interest compounded semimonthly. If you make semimonthly deposits of $50 beginning next month, how long will it take for your account to reach $4000?
Keystrokes fCLEARG 6.25\24z 775$ 50P 4000M g n 2z
0.26 775.00 50.00 4,000.00 4,000.00 58.00 29.00
Calculates and stores i. Stores PV (with minus sign for cash paid out). Stores PMT (with minus sign for cash paid out). Stores FV. Sets the payment mode to End. Number of semimonthly deposits. Number of months.
As in Example 1, it is likely that only 57 full deposits will be required, the next and final deposit being less than $50. You can calculate this final, fractional, 58th deposit as in Example 1, except that for this example you must subtract the original FV. (In Example 1, the original FV was zero.) The procedure is as follows:
Page: 42 of 209 Dimension: 14.8 cm x 21 cm

Keystrokes MM

4,027.27
Calculates FV which equals the balance in the account if 58 full deposits were made.* Recalls amount of deposits. Calculates the balance in the account if 57 full deposits were made and interest accrued during the 58th month. Calculates final, fractional, 58th deposit required to reach $4,000.

50.00 3,977.27

Calculating the Periodic and Annual Interest Rates
1. Press fCLEARG to clear the financial registers. 2. Enter the number of payments or periods, using n or A. 3. Enter at least two of the following values: Present value, using $. Payment amount, using P. Future value, using M. Note: Remember to observe the cash flow sign convention.
4. If a PMT was entered, press g or g to set the payment mode. 5. Press to calculate the periodic interest rate. 6. To calculate the annual interest rate, key in the number of periods per year, then press.

Sets calculator to Run mode. Display shows number previously calculated. Keys in price of typewriter. Net cost of typewriter. Keys in list price of chair. Net cost of chair.
Thats all there is to creating and running simple programs! But if you want to use programs frequently, youll want to know more about programming such as how to check what keystrokes are stored in program memory, how many keystrokes can be stored in program memory, how to correct or otherwise modify programs, how to skip keystrokes when running a program, and so on. Before you can understand these aspects of programming, we need to briefly discuss how keystrokes are treated by the calculator when they are stored in Program mode and when they are executed in Run mode.

Program Memory

Keystrokes entered into the calculator in Program mode are stored in program memory. Each digit, decimal point, or function key is called an instruction and is stored in one line of program memory usually referred to simply as a program line. Keystroke sequences beginning with the f, g, ?, :, and i prefix keys are considered to comprise a complete instruction and are stored in only one program line. When a program is run, each instruction in program memory is executed that is, the keystroke in that program line is performed, just as if you were pressing the key manually beginning with the current line in program memory and proceeding sequentially with the higher-numbered program lines. Whenever the calculator is in Program mode (that is, whenever the PRGM status indicator in the display is lit), the display shows information about the program line to which the calculator is currently set. At the left of the display is the number of the program line within program memory. The remaining digits in the display comprise a code that indicates what instruction has been stored in that program line. No code is shown for program line 00, since no regular instruction is stored there.
Page: 90 of 209 Dimension: 14.8 cm x 21 cm
Identifying Instructions in Program Lines

Program line 00

Executing a Program One Line at a Time
Pressing repeatedly with the calculator in Program mode (as described earlier) enables you to verify that the program you have stored is identical to the program you wrote that is, to verify that you have keyed the instructions in correctly. However, this does not ensure that the program you wrote calculates the desired results correctly: even programs created by the most experienced programmers often do not work correctly when they are first written. To help you verify that your program works correctly, you can execute the program one line at a time, using the key. Pressing while the calculator is in Run mode advances the calculator to the next line in program memory, then displays that lines number and the keycode of the instruction stored there, just as in Program mode. In Run mode, however, when the key is released the instruction in the program line just displayed is executed and the display then shows the result of executing that line. For example, to execute the program stored in the calculator one line at a time: Keystrokes fs Display

124.25

Sets calculator to Run mode and to line 00 in program memory. (Display shown assumes results remain from previous calculation.) Keys in price of typewriter.

625. 01625.00

36 Program line 01: \
Result of executing program line 01.

2 Program line 02: 2.

Page: 96 of 209 Dimension: 14.8 cm x 21 cm

Keystrokes

Result of executing program line 02.

5 Program line 03: 5.

Result of executing program line 03.

04156.25

25 Program line 04: b
Result of executing program line 04.

05468.75

30 Program line 05: Result of executing program line 05.

5 Program line 06: 5

Result of executing program line 06.

07473.75

40 Program line 07: +
Result of executing program line 07 (the last line of the program).
Pressing g while the calculator is in Run mode sets the calculator to the previous line in program memory, then displays that lines number and the keycode of the instruction stored there, just as in Program mode. In Run mode, however, when the key is released the display again shows the same number as it did before g was pressed: no instruction in program memory is executed.

85. 2,040.00 137.70 2,177.70 345. 1,725.00 116.44 1,841.44 5,967.70 402.82 6,370.52
Third item. AMOUNT for third item. TAX for third item. TOTAL for third item. Fourth item. AMOUNT for fourth item. TAX for fourth item. TOTAL for fourth item. Sum of AMOUNT column. Sum of TAX column. Sum of TOTAL column.
Program execution is also automatically halted when the calculator overflows (refer to page 73) or attempts an improper operation that results in an Error display. Either of these conditions signifies that the program itself probably contains an error. To determine at which program line execution has halted (in order to locate the error), press any key to clear the Error display, then press fs to set the calculator to Program mode and display that program line. You may also want to display the current program line (by pressing fs) if your program has halted at one of several t instructions in your program and you want to determine which one that is. To continue executing the program afterward: 1. Press fs to set the calculator back to Run mode. 2. If you want to resume execution from the program line at which execution halted rather than from line 00, press gi followed by two digit keys that specify the program line desired. 3. Press t to resume execution. Stopping Program Execution Manually. Pressing any key while a program is running halts program execution. You may want to do this if the calculated results displayed by a running program appear to be incorrect (indicating that the program itself is incorrect). To halt program execution during a pause in a running program (that is, when u is executed), press any key. After stopping program execution manually, you can determine at which program line execution has halted and/or resume program execution as described above.
Page: 102 of 209 Dimension: 14.8 cm x 21 cm

Section 9

Branching and Looping
Although the instructions in a program normally are executed in order of their program line numbers, in some situations it is desirable to have program execution transfer or branch to a program line that is not the next line in program memory. Branching also makes it possible to automatically execute portions of a program more than once a process called looping.

Page: 107 of 209 Dimension: 14.8 cm x 21 cm
108 Section 9: Branching and Looping
The program line immediately following that containing the conditional test instruction can contain any instruction; however, the most commonly used instruction there is i. If a i instruction follows a conditional test instruction, program execution branches elsewhere in program memory if the condition is true and continues with the next line in program memory if the condition is false.
Example: The following program calculates income tax at a rate of 20% on incomes of $20,000 or less and 25% on incomes of more than $20,000. To conserve program lines, the program assumes that the test value 20,000 has been stored in register R0 and the tax rates 20 and 25 have been stored in registers R1 and R2, respectively.
Note: If a program requires that certain numbers be in the X- and
Y-registers when instructions such as o are executed, it is extremely helpful when writing the program to show the quantities in each register after each instruction is executed, as in the following diagram.
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Well key the income into the display before running the program so that it will be in the X-register when the :0 instruction in program line 01 is executed. This instruction will place the test value 20,000 in the X-register and (as explained in Appendix A) move the income into the Y-register. The ~ instruction in program line 02 will exchange the numbers in the X- and Y-registers (as also explained in Appendix A): that is, it will place the income back into the X-register and place the test value into the Y-register. This is necessary because when either the :2 instruction in line 05 or the :1 instruction in line 07 is executed, the number in the X-register is moved into the Y-register; if the ~ instruction were not included, the test value 20,000, rather than the income, would be in the Y-register when the b instruction in line 08 is executed. Keystrokes fs Display
02 Sets calculator to Program mode.
(Display shows program line at which execution was halted at end of preceding example.)

fCLEAR :0 ~ go

0001020343 45

Clears program memory.

0 Recalls test value into X-register and
places income in Y-register.
34 Places income in X-register and test

value in Y-register.

34 Tests whether number in X-register
(income) is less than or equal to number in Y-register (20,000).
Page: 109 of 209 Dimension: 14.8 cm x 21 cm
110 Section 9: Branching and Looping
Keystrokes gi07 :2 gi08 :1 b fs

04- 43, 33 0545

??f :1 ?3 :$ ~ $ :n :1

DISPLAY 44 44
KEYSTROKES 2 :f 30 t 1 ?=?=gi:gu 13 :$ 34 :M :gifs 28293031-

DISPLAY 30

32-44 33-44

34-43, 45

1. Key in the program. 2. Press fCLEARG. 3. Key in the book value then press $. 4. Key in the salvage value then press M. 5. Key in the life in years (an integer) then press n. 6. Key in the year desired then press \.
Page: 142 of 209 Dimension: 14.8 cm x 21 cm
7. Key in the number of months in first year* then press t. The display will show the amount of depreciation for the desired year. If desired, press ~ to see the remaining depreciable value, then press :$:3= ~-:M- to find the total depreciation through the current year. 8. Press t for the amount of depreciation then, if desired, press ~ for the remaining depreciable value for the next year. Repeat this step for the following years. 9. For a new case press gi00 and return to step 2. Example: A commercial movie camera is purchased for $12,000. If maintained properly, the camera has a useful life expectancy of 25 years with $500 salvage value. Using the sum-of-the-years-digits method, what is the amount of depreciation and the remaining depreciable value for the 4th and 5th years? Assume the first depreciation year is 11 months long. Keystrokes fCLEARG 12000$ 500M 25n 4\ 11t ~ t ~ Display
12,000.00 500.00 25.00 4.00 4.00 781.41 8,238.71 5.00 746.02 7,492.69
Book value. Salvage value. Life. Year desired. Fourth year: depreciation, remaining depreciable value. Fifth year: depreciation, remaining depreciable value.
Page: 143 of 209 Dimension: 14.8 cm x 21 cm
144 Section 13: Investment Analysis
Full- and Partial-Year Depreciation with Crossover
When calculating declining-balance depreciation it is often advantageous for tax purposes to switch from declining balance to straight-line depreciation at some point. This hp 12c program calculates the optimum crossover point and automatically switches to straight-line depreciation at the appropriate time. The crossover point is the end of the year in which the declining-balance depreciation last exceeds or equals the amount of straight-line depreciation. The straight-line depreciation is determined by dividing the remaining depreciable value by the remaining useful life. Given the desired year and the number of months in the first year, this program calculates the depreciation for the desired year, the remaining depreciable value, and the total depreciation through the current year.
fs fCLEAR z ?6 :n ~ ?4 d ??-0 ?2 ?3 f# :6

Keystrokes 48?0 15\ 12z?1 22000?2 30b?3 4?4t

Monthly interest rate.

487.29
Monthly payment received by lessor.
Page: 157 of 209 Dimension: 14.8 cm x 21 cm

158 Section 14: Leasing

Example 2: Using the information from example 1, what would the monthly payments be if the lessor desired a yield of 18% annually? Keystrokes Display

18\12z ?1t

From previous example. Monthly interest rate. Monthly payment received by lessor.

1.50 520.81

Solving For Yield
Solving for yield is essentially the same as solving for Internal Rate of Return (IRR). The keystrokes are as follows: 1. Press fCLEARH. 2. Key in the amount of the first cash flow then press gJ. This initial amount is the difference between the initial loan amount and any payments received at closing time. Observe the sign convention: positive for cash received and negative for cash paid out. 3. Key in the amount of the first cash flow then press gK. Then key in the number of times that cash flow occurs then press ga. 4. Key in 0gK then the number of advance payments minus one. Then press ga. 5. Key in the residual then press gK. Then press fL to solve for periodic yield. Example: Equipment worth $5000 is leased for 36 months at $145 per month. The lessee has agreed to pay the first and last months payments in advance. At the end of the lease, the equipment may be purchased for $1500. What is the annual yield to the lessor if the equipment is purchased?
Keystrokes fCLEARH 5000\ 145\2
Page: 158 of 209 Dimension: 14.8 cm x 21 cm
Keystrokes =gJ 145gK34ga 0gK 1500gK fL12
4,710.00 34.00 0.00 1,500.00 18.10
Net amount of cash advanced. Thirty-four cash flows of $145.00. Thirty-fifth cash flow. Thirty-sixth cash flow. Annual yield to lessor.
Page: 159 of 209 Dimension: 14.8 cm x 21 cm

Section 15

Savings
Nominal Rate Converted to Effective Rate
Given a nominal interest rate and the number of compounding periods per year, this keystroke procedure computes the effective annual interest rate. 1. Press g and fCLEARG. 2. Key in the annual nominal rate as a percentage, then press \. 3. Key in the number of compounding periods per year, then press nz. 4. Key in 100 then press \$. 5. Press M+ to obtain the effective annual interest rate. Example 1: What is the effective annual interest rate if the annual nominal rate of 51/4% is compounded quarterly? Keystrokes Display g fCLEARG 5.25\ 4nz 100\ $M+

30/360 Day Basis

DAYS = f(DT2) f(DT1) f(DT) = 360 (yyyy) + 30mm + z for f(DT1) if dd1 = 31 then z = 30 if ddthen z = dd1 for f(DT2) if dd2 = 31 and dd1 = 30 or 31 then z = 30 if dd2 = 31 and dd1 < 30 then z = dd2 if dd2 < 31 then z = dd2
Page: 187 of 209 Dimension: 14.8 cm x 21 cm
188 Appendix D: Formulas Used
Reference: Spence, Graudenz, and Lynch, Standard Securities Calculation Methods, Securities Industry Association, New York, 1973. DIM DSM DCS E DSC N CPN YIELD PRICE RDV = days between issue date and maturity date. = days between settlement date and maturity date. = days between beginning of current coupon period and settlement date. = number of days in coupon period where settlement occurs. = E DCS = days from settlement date to next 6month coupon date. = number of semiannual coupons payable between settlement date and maturity date. = annual coupon rate (as a percentage). = annual yield (as a percentage). = dollar price per $100 par value. = redemption value.
For semiannual coupon with 6 months or less to maturity:
CPN 100(RDV + 2 ) DCS CPN PRICE = 2 100 + ( DSM YIELD ) E E 2
For semiannual coupon with more than 6 months to maturity:
RDV PRICE = DSC 1+ YIELD N 1+ E 200 CPN N 2 + DSC K =1 YIELD K 1+ E 1+ 200

CPN DCS E 2

Page: 188 of 209 Dimension: 14.8 cm x 21 cm

Depreciation

L SBV SAL FACT j DPNj RDVj RBVj Y1 = assets useful life expectancy. = starting book value. = salvage value. = declining-balance factor expressed as a percentage. = period number. = depreciation expense during period j. = remaining depreciable value at end of period j = RDVj1 DPNj where RDV0 = SBV SAL = remaining book value = RBVj1 DPNj where RBV0 = SBV = number of months in partial first year.

Keyboard function:

DPN J =
SBV SAL for j = 1, 2, , L L
Program for partial first year:

DPN1 =

SBV SAL Y1 L 12 SBV SAL for j = 2, 3, , L DPN J = L

DPNL + 1 = RDVL

SOYDk =

(W + 1 W + 2F ) )( 2

where W = integer part of k F = fractional part of k. (i.e., for k = 12.25 years, W = 12 and F = 0.25). Keyboard function:
(L j + 1 ) (SBV SAL ) SOYDL
Page: 189 of 209 Dimension: 14.8 cm x 21 cm
190 Appendix D: Formulas Used
Program for partial year:
L Y1 DPN1 = (SBV SAL ) SOYD 12
LADJ j + 2 (SBV D1 SAL ) for j 1 DPN j = SOYD LADJ Y1 where LADJ = L 12

DPN j = RBVj 1