Any Excel nerds out there?

I've made an IF function, which assigns various text values to different numbers. If, in the function, I have the actual numbers and do a fill down, no problem. However, I want to be able to change the criteria without opening the function so have assigned the criteria to a cell, thereby enabling me to edit the cell and change the boundaries easily. But when I do a fill down with that it moves the cells down one as well.

This is the function:
=IF(R2>=R60,"4a",IF(R2>=R61,"3a",IF(R2>=R62,"3b",IF(R2>=R63,"3c","2a"))))

When I fill down, R2 changes correctly to R3 and so on, but R60 to R63 ALSO change to R61 and so on, thereby rendering the function full of blank cells after a bit.

Posted By: APB, Sep 12, 21:25:15