Looking for an excel Formula

[rbrowntristatebattery]

I have a spread sheet where I am tracking my sales vs. my budget. My weekly budget is the same all month, so I need to have the cell calculate the following. 

Week 2 is Cell G10 minus I26*2 then divided by I26*2. 

Week 3 would be E21 minus I26*3 then divided by I26*3 

I just cant seem to find the right formula to get the percentage to come out correctly. 

[#2]

@rbrowntristatebattery 

That would be

=G10/($I$26*2)-1

and

=E21/($I$26*3)-1

But why the jump from G10 to E21? Is there a pattern to that?

[#3]

Thank you for the help.
The jump is the way the sheet is laid out. Reads like a book left to right top to bottom. Has up to 5 weeks. Very simple, but it works for my needs.

[#4]

@rbrowntristatebattery 

I think you'll have to do the formulas as in my previous reply.

[#5]

@rbrowntristatebattery 

=OFFSET($G$10,(COLUMN(K1)-COLUMN($K$1))*11,(COLUMN(B1)-COLUMN($B$1))*(-2))/$I$26*COLUMN(B1)-1

Does this formula return the intended results? The formula is in cell J26 and filled to the right.