Formula to test for bold text or not

Hi,

I'm using a sheet where some values are estimates, some are actual values and some are calculations done on the other to types of values. When I go from an estimate to an actual value, I make that cell bold, estimates being non-bold. The cells that do calculations do the calulations even if the fields are estimats and/or actual values (Some may be real, some estimates).

What I would like to do, is to make calculation cells go bold when all the cells ut uses to calculate the result are bold. Is there a formula that returns true if a specified cell is bold, and false if not?

Hope someone could help... It would make my spread sheet much more managable :)