How do I count the number of dates found in an array of dates, for a given
month. In addition, I do not wish to count any dates that occur in future
months.

Right now my formula looks like this, where "my_dates" is a range on another
worksheet containing dates, and "given_mo_yr" is a given Month/Year date.

{COUNT(IF(YEAR(my_date)=YEAR(given_mo_yr),IF(MONTH (my_date)=MONTH(given_mo_yr),IF(MONTH(my_date)<=MO NTH(NOW()),my_date))))}

The problem with this is that it counts dates that occur in the future, and
my goal is to not count those dates until it is that month.