|Read up on the VLOOKUP function in the Excel Help files.|
You can build a Lookup Table and pull the correct text value from the table based on the percentage in the cell.
Since I assume that each Text value is associated with a range of percentages, you are going to want to set the range_lookup to TRUE or 1 and sort your look up table.
It's all explained in the Help files.
Another option is a brute force Nested IF statement:
=IF(A1 >= .95, "Excellent", IF(A1 >= .9, "Good", IF(A1 >= ... etc.
The VLOOKUP method is more elegant and allows you to change just the table if the rating/text associations change. With the IF statement, you would have to edit every formula to use the new values.
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