IF formula combination

Hi,

I would like your help with a formula in Excel 2007.

I have to calculate the following: PREV = VND * NSF * GROWTH

But there can more than one choice for the values:

- VND: analysis of the month value; if this is empty then analysis the average; if the average is blank then returns “No data”
- NSF: analysis of the month value; if this is empty then analysis the average; if the average is blank then the value is 1
- GROWTH: analysis of the month value; if this is empty then analysis the average; if the average is blank then the value is 1

You can find in the excel file attached the formulas that are possible to exist.

Thanks in advance for your help.