My first reference value is in A2 (that has -5)
I selected B2:K11 and in the Conditional Formatting dialog used
Formula Is =B2-$A23 and set font colour to red
For the second one I used
Formula Is =$A2-B23 and set font colour to blue
You must have numbers in all cells
but you could use Custom Format of: 0 "°C" to display -5 as -5°C
best wishes
--
Bernard V Liengme
Microsoft Excel MVP
http://people.stfx.ca/bliengme
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"Rezendes" wrote in message
...
I am testing 10 thermometers and using Excel for my data. There is a +/-3°
allowable tolerance. Column A is my set scale (-5°C to +5°C) and columns B
through K are my result figures for these devices. I'd like to
conditionally
format the cells of the results that are too low (-3) blue and if they
are
too high (+3) format the red.

Thank you for your help in advance!