Conditional Formatting Rules

The attached spreadsheet is something I'm putting together for a project. Right now I've only applied conditional formatting to Column A, but will be using similar rules in each column. Before I went forward, I checked to make sure the rules worked.

The rules are:
Row 2: If blank, highlight yellow.
Row 3 and on: If the cell above is filled in, then highlight yellow. Once this cell is filled in, clear yellow.

So if A2 = 19, then A3 turns yellow. Once A3 changes to 80, then it clear the yellow and A4 changes yellow. This repeats.

The trouble I'm having, though, is that if A2 = ABC (text), then A3 does not change to yellow and I don't understand why. Does conditional formatting only apply to numbers? If not, how do I alter the rules to apply to text and numbers?

Maintenance Site List.xlsx

Hi,

See your file, two rules applied to column A where cells have boarders.

Regards,