Conditional Formatting based on percentage changes from old to new data

[jmck7654]

Hi,

I have seen a thread here with very similar title but I believe my problem is different...

I have data in sets of 3 columns with column A being old, B being the new value and C being the change from old to new (i.e. B-A). There are 24 of these triplets of columns going across the page. I would like Excel to colour the cells based on the percentage change that C represents from A. If C is a decrease from A, the cell should be green (this is the easy one). If C represents a change of +20% or less from A, it should be yellow, and changes of greater than 20% should be red.

For example,

A B C
10 12 2

This represents a 20% increase so cell C2 should go yellow.

A B C
36 50 14

This represents a 39% increase so cell C2 should go red.

Any help would be greatly appreciated, I have been struggling with this for a while - my main problem is that I can't work out how to make the formula recalculate itself for the corresponding triplets of data.

Thanks

Joe

[vlady]

try it like
=$C1<=$A1*0.2
then change the logical operation to greater than
=$C1>$A1*0.2

[Tiger20]

Or
Your Green is =($B2-$A2)<0 with an Applies to of =$A$2:$C$21 presuming you have headings plus 20 rows
Your Yellow is =AND(($B2-$A2)>=0,(($B2-$A2)/$A2*100)<20) same applies to
Your Red is =(($B2-$A2)/$A2*100)>=20 same applies to