Need a formula to count the dates that occurred last month

[freeb1893]

I have a column of dates. I want to create a formula where it looks at that column of dates, and counts the number of cells where the date occurred in the month prior to today. Anyone know how to put that into a formula?

 

[NeonRedSharpie]

=sumproduct(--(isnumber(a1:a51)),--(month(a1:a51)=(month(today())-1)))

 

[freeb1893]

Perfect! Also do you know how I could do the same thing, but also reference the column/cell adjacent A1:A51, and only count if the date in the adjacent column B also occurred in the month prior to today?

=sumproduct(--(isnumber(a1:a51)),--(month(a1:a51)=(month(today())-1)))

 

[NeonRedSharpie]

=SUMPRODUCT(--(ISNUMBER(I17:I51)),--(ISNUMBER(H17:H51)),--(MONTH(H17:H51)=(MONTH(TODAY())-1)),--(MONTH(I17:I51)=(MONTH(TODAY())-1)))

You probably don't need the isnumber, it just checks to make sure a cell is not blank.

 

[Scott Huish]

=SUMPRODUCT(--(MONTH(A1:A51)=MONTH(TODAY())-1),--(MONTH(A1:A51)=MONTH(B1:B51)))

Please note that none of these formulas will check to see if the two dates are in the same year or not.

 

[freeb1893]

Hmm something is hanging up this formula. I'm getting the #VALUE! error. Below is some example data. The result of the formula should be 2.

Final Submission	Initial Start
6/5/2014	6/3/2014
6/19/2014	6/13/2014
6/26/2014	6/2/2014
6/26/2014	6/2/2014
7/17/2014	6/17/2014
7/14/2014	7/14/2014
7/2/2014	7/2/2014
7/24/2014	7/2/2014
7/30/2014	7/2/2014
8/5/2014	7/29/2014
8/22/2014	8/15/2014
8/22/2014	8/13/2014
	9/2/2014
	7/9/2014
	6/26/2014
	7/23/2014
	7/9/2014
	7/9/2014
	7/29/2014

<tbody>
</tbody><colgroup><col><col></colgroup>

=SUMPRODUCT(--(MONTH(A1:A51)=MONTH(TODAY())-1),--(MONTH(A1:A51)=MONTH(B1:B51)))

Please note that none of these formulas will check to see if the two dates are in the same year or not.