NPV range using input cells

[pma]

I want to select the number of years in an NPV calculation by using an input cell.

In this case, I have 14 years of cash flows in e47:r47. In cell b47 I want to input a value, say 5. In c47 I want to have an NPV calculation that will use whatever value I put in b47 to define the range for the NPV.

I've tried various forms of address, index and indirect funtions without success.

Thanks in advance for any suggestions!