I have a table as so:

A B C D E F G
1 Candidate Basic Car Fee % Fee 50/50 Month
2 Don Wood £32000 £5000 17.5% £6475 FALSE 3
3 Ron Kinn £44500 £5000 17.5% £8663 FALSE 3
4 Rob Simms £35000 £5000 17.5% £7000 FALSE 3
5 Jay Atkins £16000 £6000 17.5% £3850 FALSE 2
6 Ed Barry £31000 £5000 15.5% £5580 FALSE 2
7 Ron Pass £33000 £5000 17.5% £6650 FALSE 2
8 Adie Carthy £42000 £4500 12.5% £5813 FALSE 1
9 Don Carter £43000 £2000 20.0% £9000 FALSE 1

I have a 3 conditional formats that cover the whole table, relating to
the month colum saying
1) formulais: =IF($A9<"",$G9=1) then colour whole column blue
2) formulais: =IF($A9<"",$G9=2) then colour whole column red
3) formulais: =IF($A9<"",$G9=3) then colour whole column green

This is all fine and dandy until I have a month 4 to contend with.....

I have a feeling I need to use some sort of Worksheet_Change VBA type
cleverness. Which is beyond me.

Can anyone help? Please?