Incorrect conditional formatting

[pderwael]

Hi folks,

I'm having some difficulties with conditional formatting of attendance %ages

The rules I wish to apply are the following:
> 75% attendance = green
>=65% & <75% = orange
>=50% & <65% = red
<50% = black

In the attached spreadsheet, I have managed to do this with "format only cells that contain", but I wanted to make use of icon sets which are nicer

With the icons, 6 of my 18 results are incorrectly formatted and I have no clue why...

Any suggestion would be highly appreciated!