Robert,

Array enter (enter using Ctrl-Shift-Enter) the formula

=SUM(IPMT(10%/12,ROW(INDIRECT("1:9")),60,-10000,0))

The "1:9" is used to tell the function to sum the interest payments for periods 1 to 9. Next year,
you would use
10:21 for those twelve months...

HTH,
Bernie
MS Excel MVP


"Robert Golja" wrote in message
...
I have an annuity plan for let's say 5 years with 60 monthly installments
with a financing amount of 10.000 ? and 10 % interest rate. The payment plan
starts in March 2007. Is it somehow possible to calculate with a formula, how
much interest I will have to pay just for the periode from March till
December in the first year? That means only for 9 month.

Thanks in advance for your answers!
Robert