"Willing to learn" wrote:
I have the following data:
A B
Month's Net Income $
Month's Total Expense 00
Total Revenue $
Percent Revenue

I would like to have my Percent Revenue % (B4) as result of my Income
[....]
For instance, lets make a example, if I earn 50 dollars in my Income (B1) ,
but I spent 100 in (B2) I would like Percent Revenue (B4) show me -100%
otherwise, if I earn 100 and spent 50 it would show me %50

Try this:

B3: =B1-B2

B4: =B3/B1