# Excel – Why is there an error with this simple Excel formula using MOD and ROW()

microsoft excel

I'm trying to set up alternating row styling on a selection. I click on the first row and drag down to row 145 (where data ends).

Then I go into Conditional Formatting, choose new rule, and am trying to enter this formula:

=MOD(ROW(),2)=0


When I click OK, I get this not very helpful error in Excel 2016:

There's a problem with this formula.
Not trying to type a formula? When the first character is
an equal (=) or minus (-) sign, Excel thinks it's a formula.
<snip>


What is wrong with the formula?