Number less than zero is shown as a zero

edited 12/09/19 in Smartsheet Basics

Hello again community,

I am hoping someone can help me understand the right way to write this formula for what I am trying to achieve.

I am wanting to subtract one cell from another which in some cases provides a negative number. I would like the formula to pick up on this negative number and output a 0 in place of the negative number.

This is the formula I have so far that does not work.

=SUM([Column4]20 - [Column4]19) = IF([Column3]20 = <0, "0", "")

Many thanks in advance.