Hi, This might be a start:-
Calculating Repayments on Loan
This formula will return the Periodic Repayments to be made over the period specified.
Use AER Interest Rates fo "r"
P = Principle. r = Annual Interest Rate. R = (1+ r) S = Periodic repayment.
n = Period (mth etc.)
S = P ( R(n+1) - Rn )
Rn - 1
Note:- When dealing with Loans and Mortgages the normal repayment periods are months.
In these cases the 12 root of R would be used to represent a period of one month
In the example "r" = 10%, "R" = 1.1. This would be replaced by 1.1(1/ 12) = 1.00797414
If the period "n" was 3 years, "n" would equal 36 Months (3 x 12.)
In the case (n + 1). 1 is always 1 irrespective of whether the periods are months or years.
NB:- For Payments in advance, alter the bottom line of the equation to:- R(n+1) -R