Conditional formatting

[ukredskin]

I know basically how conditional formatting works, but have encountered a
slight problem. I have a column of figures (whole numbers) in which there
are some blanks. I want to use conditional formatting to change the cell
colors to RED if the number is in the range 0 to 99, ORANGE if it is -1 to
-7, and BLUE if it is below -7. This bit I can do, however, if the cell has
no value in it I need it to stay white.
The conditional formatting appears to regard having a blank cell as the same
as having a zero in it, so it changes to RED.
Is there a way round this?

 

[John C]

On the red portion, it would be something like this:
=AND(A1>=0,A1<=99,A1<>"")

 

[muddan madhu]

condition 1 =AND(A1>=0,A1<=99,A1<>"")

condition 2 =AND(A1<=-1,A1>=-7)

condition 3 =A1<-7