I'm trying to work out a formula for calculating margin of error in Excel. Had a look around Google, but didn't find what I was looking for. What I need to do is determine the percentage difference between two numbers. Let's say I project a dividend of 50 cents for a given year. However, the actual dividend is 45 cents. So the margin of error on this is about 10%, give or take (45 cents is 90% of 50 cents). Does anyone have a formula I could pinch please? Thanks in advance. Mark

"Margin of Error" has a specific statistical meaning and relates to sample sizes and error rates from survey data. I'm not sure if that's actually what you are looking for ? If you just want to calculate the percentage difference between two numbers (predicted and actual), then surely this would do the trick: A1 = prediction A2 = actual formula =(A2-A1)/A1 if the actual is less than the prediction, result will be negative. Result can be formatted as a percentage. Is that what you want? Or are you after something more statistical?

Mate, that's exactly what I needed, thanks! I was racking my brains for about an hour last night trying to work out the formula for it. Maybe I shouldn't try so hard at 3 in the morning. Mark