Unique Values by month in date range

Hi All,
First thank to all who contribute, I've found this forum to be immensely helpful. I've searched through the forums but haven't quite found a solution to my issue. I have a set of values in Col A which have a related date in Col B. What I would like to do is count unique values in A where date is in year 2013 (or other variations such as between 1/1/2013-3/31/2013). Secondly, I would like to be able to visualize by month the unique counts of A. For instance, Unique Names down vertical and Months for each year along the vertical access. Could be table, chart, pivot.

I'm attaching a sample sheet if the above doesn't quite make sense.unique values by month.xlsx

Many thanks!
Kerry

In E7, plop:

=IFERROR(INDEX($A$4:$A$56,MATCH(0,COUNTIF($E$6:E6, $A$4:$A$56),0)),"")

Which is an array formula confirmed with Ctrl+Shift+Enter instead of just hitting Enter as normal to exit the cell. Drag this down as far as needed, it will create your list.

In F7, plop:

=SUMPRODUCT(($B$4:$B$56>=F$6)*($B$4:$B$56<EOMONTH(F$6,0))*($A$4:$A$56=$E7))

And copy as far over and down as needed. This will count each unique value per month in the range.

As for PivotTable, which I am practically clueless about:

Highlight the data A3:B56, click Insert -> Pivot Table

Pull Name down to RowLabel, pull Created Date down to Column Labels, and then pull down down Created Date again to Values

Now in the pivot table, right click on the first date in the column headers. Choose "Group..." and select both Month and Year. Hit Okay.

This is the much faster version.

Hi Daffodil,
Thank you very much for the suggestion, however, it doesn't count unique Names, so if it sees multiple AA in my example xls it counts each of them.

The pivot table suggestion also doesn't count unique values. I understand that Excel 2013 does provide the ability to show unique counts, however, it won't let me group the dates by months so I can't see how many unique names show up for each month.

If it's more simple I would be happy to simply see:
Month Count
Jan 2013 3
Feb 2013 6
Mar 2013 3

Etc.

Open to any other suggestions.

Thank you again for all your help. I haven't explained what I'm trying to do articulately enough now that I see how you answered. What I'm really trying to count is how many new Names did we add each month. In my example xls the name AA was first added in 6/2013, so I wouldn't want to count it again in later months because it's already been counted.

My real data set is basically orders, so I'm trying to calculate new customers per month. Does that make more sense?

Wow, it sure does.

Unique entries out of the whole set, and the count of the new uniques, per month. Got it.

Yeah, it's a bit tricky. Been struggling with this for a few months.

How about this?

The formula for Jan 2013 counts if letters match the month.

For Feb forward, if the sum of the row so far is still zero, it does the same as Jan, and if there are numbers, it leaves it blank.

The new uniques per month are at the bottom.

unique by month.xlsx

We'll have this squared away within the hour.

Holy cow! Amazing...and elegant I might add! Daffodil, I am super impressed and very very thankful!

And there was much rejoicing!

Glad I could help. Let me know if you have any issues adapting the formula to your real data.