If you're using Format|conditional formatting to color those cells, then I think
it would be easiest to just duplicate those rules in helper cells and then use
those helper cells in your calculations.

But if you really, really want (it ain't for the faint of heart!), take a look
at how Chip Pearson does it:
http://cpearson.com/excel/CFColors.htm

If your colors are changed via format|cells (probably by an event macro????),
check this page on Chip's site:
http://cpearson.com/excel/colors.htm
look for:
Counting Cells With A Specific Color

Excel cannot find and count CF colored cells in the same manner it finds and
counts manually colored cells.

If you can't use one of the  COUNTing functions to identify cells by the values
you used to CF them, you can go to Chip Pearson's site for code to identify CF
coloring.

http://www.cpearson.com/excel/CFColors.htm

Gord Dibben  MS Excel MVP