Column A has Dates.
Column B has corresponding Amounts

I want to calculate the average amount for a specific given month.

If my data has two months in September, and the Amounts for these dates are
1.23 and 5.26 respectively, then my average for September would be
(1.23+5.26)/2.

So I need to calculate how many dates have September as the month, and the
rows they are in to get the Amounts.

Suggestions please?

Thanks,
Bernie