Escel

[Ronald_B_Wildman]

In Excel, how do I apply a constant reduction (minus) factor of 15.0 to all cells in all columns except for columns 1, 2, and 3.  There are 13 columns populated in the worksheet A thru M.

[#2]

@Ronald_B_Wildman 

To make the change in the existing columns, you must first calculate the change elsewhere, then paste it over the original data. 

This formula (adjusted for the corrected number of rows in your spreadsheet):

=D2:M11-15

Calculates the new values:

I've put the formula below the original data to make the image size more sensible, but you can put the formula wherever you want. 

You can then copy and paste values to replace the original values. Or not, if you prefer. 

[#3]

@Ronald_B_Wildman 

As variant

- put reduction factor in any cell (Q1) and copy that cell

- select desired range to which it'll be applied

- Paste->Paste Special->Subtract->Ok

Ctrl+Z if you'd like to return back right after that.