## 5.3 Modelling Annuity Investments using Technology

Note: if you cannot remember how to model reducing balance relations with regular repayments, revise notes for 5.1 Modelling Annuity Investments.

### Guide to Analysing Annuity Investments using Technology (Casio Graphics Calculator)

Note: if you cannot remember how to use the Casio Financial Calculator, revise notes for 3.3 Modelling Reducing Balance Systems with Regular Repayments using Technology.

- The
**annual interest rate**should be entered/calculated as a**positive**value. - The
**initial value (PV)**should be entered/calculated as a**negative**value (remember we justify this by saying we must lose this amount to create the investment). - The
**payment (PMT)**(i.e. the amount withdrawn) should be entered/calculated as**negative**(we can justify this by saying we lose this amount per compounding period to the investment)