One way:

A1: <budget
B1: <actual
C1: =B1/A1 - 1 (formatted as a percentage)


Select C1. Choose Format/Conditional Formatting. Use the dropdowns and
textbox to enter:

CF1: Cell value is greater than or equal to 0.1

Click Format, choose Red from the Font/Color dropdown. Click OK


In article ,
"carlton" wrote:

i need to calculate spends against budget, if there is an over spend against
budget,
ie spend is 10% over budget, i want to show the spend as (10%) and in red.