Macro stopped working in result col U .

[I need excel help]

Hello all , i have a macro that is giving me part of the code as a result . This part .

=IF(AP2=1,0,ROUNDDown(COUNTIF(BJ2:NN2,1)/(AP2-1)*100,1))

The code gives a two col result in cols U and V . V is fine but now above appears in col U .
Seems it didn't like running over 100,000 rows . But col V did ok .

Looking to where I'm going wrong . Thanks .