R1C1 keep reference cell fixed in copy

Hello,

I am having trouble with a script that is designed to normalize days from a starting value. Say column A rows 1:10 contain values 730-740. Column B should subtract A1 from each cell and then copy down to give values since value 1. (so Column B would read 0, 1, 2 ... 10.)

I understand the notation of R1C1, and I know how I could subtract the cells simply with a fixed reference to R1C1.

RC[-1] - R1C[-1]

But I am having trouble with the fact that this script needs to be started at any starting point in the sheet. So maybe the 730-740 data in Column A doesn't start at Row 1. Maybe it starts at Row 50, or just row {ROWX}.

I need the resulting code to be

RC[-1] -R{ROWX}C[-1]

.

I can, of course, get this to work for the one cell, but it needs to keep referencing R{ROWX}C[-1] when I autofill rows ROWX+1 through ROWX+9.

I hope this explains the issue. I need to autofill rows to subtract themselves

Please see attachment and ask questions.