I would suggest identifying a cell on your data worksheet (let's say A14) to be the percent of change you want to apply to the original value. It would be formatted as a percentage so that 0.1 would be formatted as 10%. Then make your formula in the Presentation worksheet say

=Range1*(1+Data!$A$14)

where Range1 is the original value.

You didn't name your first worksheet; change Data to whatever the worksheet name is.

This is exactly the kind of analysis that Excel is good at without using macros. Even though I love macros I wouldn't use them for this problem.