I’m doing a u test for a project on excel . I’m using stem heights for one varia

I’m doing a u test for a project on excel . I’m using stem heights for one variable and if mowing or unmowing has any effect on the stem heights. Every time I put rank.avg with the columns, I’m getting 0 or 1. I’m not that good at excel and there is no drop down box. I have to do 4 tests and show how you got the result. Help!!!