In the top cell of the new column where the new numbers should show up (I'll assume this is B1 with the column of old numbers starting in A1) type "=(A1-X)" where X is the number you're subtracting, and without the quotes around it. Then, highlight the entire column, starting with B1 and moving down, and then go to Edit; Fill Down. You can also click and drag down the bottom right corner of cell B1 and that does the same thing.
If you have any more excel questions, let me know, I've been using it a ton recently. A cool thing I noticed is that if you want the top row to stay visible even if you're scrolling down hundreds of cells (such as, say, looking at a bunch of baseball stats
) then all you have to do is click on Row 2 so the entire row is highlighted, and go to Window; Freeze Panes. It's so simple, but I never noticed it until a few days ago.
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