Time Value of Money Question

Hi, I am looking for help on a formula that will calculate the following.

The basic goal is to be able to input a number that has grown over time at an irregular daily rate and find the original value.

For example: If the value today (1/13/2009) were 1000 and over time it grew at the following rate.

1/10/2009 5%
1/11/2009 -2%
1/12/2009 3%

What would be the best way to calculate the value on 1/10/2009, but relatively easy enough to update daily?

Thanks for your help!