So, we use theSUMPRODUCT functionwith custom logic instead.
This is a standard number between 1-12, and the details of this formula areexplained here.
The results from these two expressions are then compared.
As the formula is copied down, it returns the total count of birthdays in each month as listed.
See theSUMPRODUCT pagefor more information about howlogical expressionswork inside SUMPRODUCT.
Pivot table solution
A pivot table is anexcellent solution for this problemas well.
