I have a spreadsheet where the even numbered rows cell shading is grey and
the odd rows cell shading is white. I use

I have numbers in my other columns where i.e. A2 is 001, A3 = 002, A4 = 003,
etc. I need to update those numbers so I change A2 to = 020 and click lower
right corner of cell to get the "+" sign and start to drag. So A3 = 021, A4
= 022, etc.

As drag all cell shading turns to grey or white depending where I start.
How to use this feature to change the number in the cell without it changing
the cell shading.

Thanks for any help.