I get - Sign when subtracting

Hello, 
I have two Columns Column 1 and Column 2. When I subtract them using data formula = Subtract [Column1]-[Column2] I get - sign.

An example can be

Column 1     Column 2
31                  113                     Answer I get is -82
I understand this is how math works but the columns I have will always have different numbers. How do I remove - sign so it will not appear? Please help.