Help with executing the formula if the cell is not empty, if empty end.

[kevinw]

I am trying to do a formula that will run when the cell has a number in it, then do a calculation and stop if it does not.
So:
If Cell A1 has an amount of 100 and Cell B1 is empty then return a Blank cell
If Cell A! has an amount of 100 and Cell B! is 90 (or 101) then run a formula deducting A1 from B1 (understand the result can be positive or negative)
If Cell A! has an amount of 100 and Cell B1 is also 100 then return text of "Nil"

I've tried with if statements but can't quite get it right.

Thanks in advance

 

[Fluff]

How about

=IF(B1="","",IF(B1=A1,"Nil",B1-A1))

 

[kevinw]

Fabulous works like a charm. Many thanks

 

[Fluff]

You're welcome & thanks for the feedback.