E-CodeLoan amortization with extra payments — a TI-84 Plus CE program
AMORT is a TI-BASIC program for the TI-84 Plus CE. Mortgage or car loan: the payment, a year-by-year balance table, total interest and total paid — and with an extra amount each payment, how much sooner it is paid off and how much interest that saves.
What it asks for and what it shows
It asks for 5 values at its prompts. In the example below it shows PMT, PAID N, YEARS, INT, TOTAL, SAVED.
Example run
One of its oracle test cases: “30-year mortgage 300000 at 6.5%”. The inputs are typed in order, and the results are the values the case expects on the screen.
| Step | Value |
|---|---|
| You enter | |
| Input 1 | 300000 |
| Input 2 | 6.5 |
| Input 3 | 30 |
| Input 4 | 12 |
| Input 5 | 0 |
| The screen shows | |
PMT= | 1896.2 |
PAID N= | 360 |
YEARS= | 30 |
INT= | 382633.47 |
TOTAL= | 682633.47 |
SAVED= | 0 |
How it's checked
6 test cases, each checked against an independent method. Replayed key by key on a virtual TI-84 Plus CE, they make 43 checks.
How E-Code checks every program
Run it or put it on your calculator
- Open the library in the TI-84 Plus CE calculator and pick “Loan amortization with extra payments” (AMORT).
- Put it on your own calculator with a computer and a USB cable, or type it in by hand.
Related programs
- Compare two loans (APR with fees)
- Compound interest calculator
- Time value of money solver (N, I%, PV, PMT, FV)
- NPV, IRR, MIRR and payback
- Depreciation schedule: SL, 200% DB, SYD
All TI-84 Plus CE finance programs · All TI-84 Plus CE programs