Moreden,

If you add to the principal at a constant rate, and the interest rate
doesn't change, then simple use the FV function. Otherwise, you need to use
a stepwise method, using a table of variable inputs to FV at every change in
rate or principal addition.

HTH,
Bernie
MS Excel MVP


"Moreden" wrote in message
...
Hi folks,
Would appreciate some help in locating a formula to calculate compound
interest on an increasing principal.
Many thanks