Finance Application for the TI-89 / TI-92 Plus Important Information Where to Find Installation Instructions The Time-Value-of-Money (TVM) Solver Editing Values in the TVM Solver Calculating TVM Outside of the TVM Solver Finance Functions Calculating Cash Flows Calculating Amortization Calculating Interest Conversion Finding Days between Dates Defining Payment Method Finance Examples Example 1 — Financing a Car Example 2 — Calculating Interest on a Fixed Payment Example 3: — Amortization Error Messages E
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Where to Find Installation Instructions For detailed instructions on installing this and other Flash applications, point your web browser to: http://www.ti.com/calc/docs/guides.htm Installing this application requires TI-GRAPH LINKé. To download a free copy of TI-GRAPH LINK for the TI-89 / TI-92 Plus, Point your web browser to: http://www.ti.com/calc/docs/link.
The Time-Value-of-Money (TVM) Solver Use Time-Value-of-Money (TVM) functions to analyze financial instruments such as annuities, loans, mortgages, leases, and savings. The TVM Solver screen automatically displays when you run the Finance application. It displays the time-value-of-money (TVM) variables: Ú, æ, PV, PMT, FV. Given four variable values, the TVM Solver solves for the fifth variable. To access the variables outside the TVM editor, press 2 °. They are located in the Finance folder.
2. Enter the known values for N, I%, PV and FV. Press D or ¸ to save each new value. 3. Enter a value for PpY, which automatically enters the same value for CpY; if PpY ƒ CpY, enter a unique value for CpY. 4. Select END or BEGIN to specify the payment method by highlighting the option with the cursor and pressing ¸. 5. Place the cursor on the TVM variable for which you want to solve (i.e. PMT). 6. Press „ Compute. The answer is computed and displayed and stored to the appropriate TVM variable.
To clear all TVM variable values and reset all options to their defaults, select 8:Clear Editor. To find out the application software version of the application, select A: About. Press N or ¸ to close the screen. Calculating TVM Outside of the TVM Solver All TVM and finance functions are listed in the ½ for use outside of the TVM Solver. Each TVM function takes zero up to six arguments. Function calculations outside the TVM Solver do NOT save the results in memory.
tvm_PV The tvm_PV function calculates the present value. tvm_PV(N,I,PMT,FV,PPY,CPY) tvm_Pmt The tvm_Pmt function calculates the amount of each payment. tvm_Pmt(N,I,PV,FV,PPY,CPY) tvm_FV The tvm_FV function calculates the future value of money. tvm_FV(N,I,PV,PMT,PPY,CPY) Finance Functions Catalog This application adds all Finance functions to the catalog for use in calculations outside of the TVM Solver.
Sending the Application to Another Calculator with Var-Link If you send the Finance application to another calculator, the other calculator receives the application, including all finance functions as well as the TVM variables defined to their default values (not as they might be currently defined). If you want to send stored variable values, first send the application, then send the variables using 2 °. Note: After pressing 2 °, the finance variables are listed in the Finance folder.
Calculating Amortization Use the amortization functions (bal, GPrn,GPrn) to calculate balance, sum of principal, and sum of interest for an amortization schedule. Catalog Variables/ Arguments Definition (for an amortization schedule) bal(npmt[,roundvalue]) Schedule balance; based on stored values for I, PV, PMT, PpY, and CpY. ΣInt(PMT1,PMT2[,roundvalue]) The sum of the interest during a specified period. Based on stored values for I, PV, PMT, PpY, and CpY.
Finding Days between Dates Use the date function dbd( to calculate the number of days between two dates using the actual-day-count method. Catalog Variables/ Arguments dbd(date1,date2) Definition Number of days between 2 dates. ¦ date1 and date2 can be numbers or lists of numbers within the range of the dates on the standard calendar. If both date1 and date2 are lists, they must be the same length. ¦ date1 and date2 must be between the years 1950 through 2049.
Finance Examples Example 1 — Financing a Car You have found a car you would like to buy. The car costs $9,000. You can afford payments of $250 per month for four years. What annual percentage rate (APR) will make it possible for you to afford the car? 1. Press 3. Press D D B 3 to highlight FIX 2. Press ¸ ¸ to return to previous screen. 2. Press O 1: FlashApps ¸. 3. Highlight Finance with the cursor and press ¸ to open the application. The TVM Solver is displayed. 4.
Example 2 — Calculating Interest on a Fixed Payment At what annual interest rate, compounded monthly, will $1,250 accumulate to $2,000 in 7 years? Note: Because there are no payments when you solve compound interest problems, PMT must be set to 0 and PpY must be set to 1. 1. Press 3. Press D D B 3 to highlight FIX 2. Press ¸ ¸ to return to previous screen. 2. Press O 1: FlashApps ¸. 3. Highlight Finance with the cursor and press ¸ to open the application. The TVM Solver is displayed. 4.
Example 3: — Amortization You want to buy a home with a 30-year mortgage at 8% APR. Monthly payments are $800. Calculate the outstanding loan balance after each payment and display the results in a graph. 1. Press 3. Press D D B 3 to highlight FIX 2. Press ¸ ¸ to return to previous screen. 2. Press O 1: FlashApps ¸. 3. Highlight Finance with the cursors and press ¸ to open the application. The TVM Solver is displayed. 4. Press 3. Press B D to highlight PARAMETRIC graphing mode. 5.
9. Press ¥ # to display the parametric Y= editor. Turn off all stat plots. 10. Press Ü ¸ to define XT 1 as T. 11. Press ½ … and highlight bal(. Press ¸ Ü d ¸ to define YT 1 as bal(T). 12. Press ¥ $ to display the window values. Enter the values below: Tmin=0 Tmax=360 Tstep=12 Xmin=0 Ymin=0 Xmax=360 max=125000 Xscl=50 Yscl=10000 13. Press ¥ % to draw the graph. 14. Press … Trace to activate the trace cursor. Press B and A to explore the graph of the outstanding balance over time.
Error Messages Message Description No Sign Change You attempted to compute I when FV, (N†PMT), and PV are all ‚ 0, or when FV, (N†PMT), and PV are all 0. You attempted to compute irr( when no elements of CFList nor CFO is > 0, or when no elements of CFList nor CFO < 0. One or more TVM Solver variables are invalid. Press Enter to overwrite or Escape to return to the Home screen. TVM Solver variable is locked or archived. Can not overwrite variable. Exiting application.
Error Recovery Instructions Low Battery Condition Do not attempt a Flash download if the low-battery message appears on the calculator. Low battery indication is shown on the initial screen. If you receive this error during an installation, change the batteries before trying again. Memory or Full Memory Error This error occurs when the TI-89 / TI-92 Plus does not have sufficient memory to store the application.
Miscellaneous Verify Maintenance Upgrade Version and Serial Number 1. From the Home screen, press ƒ. 2. Select A:ABOUT. The version number has the format x.yy. The serial number appears on the line beneath the product ID number. Check Amount of Flash Application Free Space 1. Press 2 ¯. 2. Select 2:MEM MGMT/DEL... The Finance application requires at least 36K of RAM memory to load the application. There is approximately 720K total archive memory in the TI-89 / TI-92 Plus.
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