MaxIf using Ranges, #N/A error

I trying to find the max of the number in range FY12District that have the criteria of 1 in range FY12UnDaysOut using range names. The ranges are the same size. I'm getting a #N/A error.

1 15
1 10
2 5
1 6
2 20

Answer would be 15

=MAX(IF(FY12District=1,FY12UnDaysOut)) using Ctrl, Shift, Enter