Average over a dynamic range of values in a different worksheet

Hi,

My problem is this:

I want to use the Range("E1"). Formula = "Average..." formula to calculate a dynamic average on another worksheet in the same workbook. The range will be determined by what users enter into a specific cell. And though the column of data (E) is the same it is the rows that change. I can do this easily using the formula:

Sheets("Calculations").Activate
Range("E1").Value = Application.WorksheetFunction.Average(Sheets("Template").Range("E" & Zprow & ":E" & Iprow - 1))

However, when this runs it doesn't display the function in the cell on the worksheet and for transparency this is what I need.

Is this clear? I really hope someone can help as I'm pulling my hair out looking for solutions on the web.

Many thanks in advance.