I need to calculate the number of months within a year if that year falls within a date range. 10/1/2010 to 8/15/2017 how many months for each column of 2010, 2011, 2012,2013,2014,2015,2016,2017 so 2010 would return 3, the rest would return 12, and 2017 would return 8 months

0

May be an easier solution, but the following formula works :

```
=IF(AND(D$2 >= YEAR($B3);D$2 <= YEAR($C3));IF(D$2=YEAR($B3);12-MONTH($B3);IF(D$2=YEAR($C3);MONTH($C3);12));0)
```

With years on the second line, start dates in the B column and end date in the C column.