Hi, This might be a start:-

Calculating Repayments on LoanThis 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 = PNote:- When dealing with Loans and Mortgages the normal repayment periods are months.( R(n+1) - Rn )Rn - 1

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

Regards Mick