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Hi Janet,

I am two numbers: a forecast number and an actual number. I'd like to measure the percent difference of the actual number in relation to the forecast number. I'd like to be able to say "The forecast number was x% higher/lower than the actual number." And, if different, "The actual number was x% higher/lower than the forecast number."

The numbers will be positive, negative, and in some cases zero.

Sample Data:

Forecast Number Actual Number

161 157

74 0

24 -12

-4 143

Thanks for your time!

It's easier to show than to explain.

Forecast = 161

Actual = 157

Expressing forecast as a percentage of actual:

difference = forecast - actual = 161 - 157 = 4

difference/actual = 4/157 ≅ 0.0255 = 2.55%

The forecast was 2.55% higher than the actual.

Expressing actual as a percentage of forecast:

difference = actual - forecast = 157 - 161 = -4

difference/forecast = -4/161 ≅ -0.0248 = -2.48%

The actual was 2.48% lower than forecast.

The others are calculated the same way.

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