
Appendix G


HP80 Calculation Formulas


Unless otherwise stated: 
n

=

Number of time periods
 


i

=

periodic interest rate expressed as a decimal
 


PMT

=

payment or deposit
 


PV

=

present value or principal
 


FV

=

future value
 


I

=

interest amount
 


Compound Interest




Annuity




Add on Interest Rate to Annual Percentage Rate


r = decimal Add on rate




APR = 1200iWhere i is the solution for the above equation.


Bond Calculations


n

=

total number of days between purchase and maturity
 

INTR

=

decimal coupon rate (on annual basis)
 

YTM

=

annual yield to maturity in decimal
 

Bond

=

bond price
 


If n < 182.5



