Formula correction? IF ...

I have a spreadsheet that gives error percentages in column F - I want to categorise these percentages into bands as follows -

0-10 Excellent
10-20 Good
20-60 Low
60-80 Very Low
80 and above Concern

I've made a start with the following, but the result is always Excellent, despite the figure in the F column. Can anyone help me with a correction or a more effective way of getting the desired outcome?

=IF(F5>=80%, "Concern", IF(F5>=60, "Very Low", IF(F5>=20, "Low", IF(F5>=10, "Good", IF(F5<10, "Excellent")))))

Hi,
Please attach your excel file...

File uploaded remove confidential data - now looking for column A to be based on % in column C

You need to add the percent sign to all the numbers
=IF(C3>=80%, "Concern", IF(C3>=60%, "Very Low", IF(C3>=20%, "Low", IF(C3>=10%, "Good", "Excellent"))))

Provide another method for reference
A3 cell formula , drag down

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