If month's income is in A2, and the whatever amount you have is in a1, % of
month's income is:

=a1/a2

Format as percent.

Regards,
Fred.

"Jill" wrote in message
...
What formula do I use to find "% of month's income". I have Net Sales,
Royalty, Manufac. Costs, Advertising, and Net Income (B4-F4).