Indexation help needed

Having a few problems with an application I'm trying to write at the moment, and hoped you guys could help

I have a value of an object, £x which is input at outset by the user
I have a value by which this object will grow by every year, y%, again chosen by the user
I have a value assumed for inflation, z%, chosen by the user as above

I've worked out all the growth calculations fine, but now I need to index the value at the end of each year by the appropriate rate of inflation.....sounds simple and you can do it in 2 seconds on a calculator, but causing me problems on Excel

For example - initial value is £200,000
Grows by 7% in 1 year, new value is £214,000
Inflation is assumed to be 2%, therefore adjusted value is £209,720 (ie. what £214,000 would be worth in today's terms)

Easy so far.........difficult bit is next year and so on and compounding the 2%

The function which would do the job is 'fvschedule' - input the initial value then a range of interest rates as assumed future growth (or negative for inflation).........this would be absolutely perfect but for some reason will not allow you to reference cells as the range of interest rates, you have to physically enter numbers ?????

I want to be able to reference a cell, as one of the functionalities is that the assumed rate of inflation can be changed as opposed to being fixed into the programming

I have tried nesting the above function which works, but only to the maximum 7 'nests' allowed........I need a range covering 20 years

Any help much appreciated

Thanks

Matt

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