Hi, sorry for posting this twice but i wasn't sure which category it fell under!

I have a slight problem with excel and and was wondering if anyone can help.

I have 3 columns, A, B, C:

Column A= Uncorrected Number
Column B= Correction Factor
Column C=Corrected Number (Column A-ColumnB)

Column A Column B Column C
2.40 0.51 1.89
2.45 0.49 1.96
2.47 0.55 1.92

Problem:

In Column C, the value in any Cell cannot be less than the number before it! ie, row 3 is incorrect and should be 1.961 or greater etc.

I've tried using a goal seek function but it does not allow me to solve it for an equation, for example setting my to value as being C2>C1. Can anyone help me with this problem? It would be much appreciated. Thanks