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 Question from Reuel: Hello: I'm looking for an answer to this one: If I have 428 staff for Performance Appraisal the year 2011 my suggestions for rating their rankings would be: 5% can be no. 1 which would mean 21 employees 15% can be no. 2 which would mean 64 employees 60% can be no. 3 which would mean 257 employees 15% can be no. 4 which would mean 64 employees 5% can be no. 5 which would mean 21 employees However, what I have received is this: 5% are no. 1 which would mean 20 employees 22 % are no. 2 which would mean 94 employees 60% are no. 3 which would mean 270 employees 15% are no. 4 which would mean 41 employees 5% are no. 5 which would mean 3 employees Now my question is how do I find the percentage difference between both the scenarios of should be versus reality? I don't think it is normal subtraction, is it? any help would be appreciated. Best Regards, Reuel

Hi,

Should what you received say the following?

5% are no. 1 which would mean 20 employees
22% are no. 2 which would mean 94 employees
63% are no. 3 which would mean 270 employees
10% are no. 4 which would mean 41 employees
1% are no. 5 which would mean 3 employees

If so then since all the percentages you have are percentages of the same number, 428, you can make direct comparisons. You could for example say

The number of employees receiving a performance rating of 2 is 7 percentage points more that I expected.

and

The number of employees receiving a performance rating of 4 is 5 percentage points less that I expected.

Does this help?
Harley

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