Count Unique Values Based on Criteria

I need to count the number of unique values in Column B based on criteria found in Column A

Column A     Column B
Sally               item 1
Sally               item 1
Sally               item 2
Jerry              item 4
Mark               item 5
Mark               item 5
Mark               item 6
Mark               item 7
Mark               item 7

So Sally would have 2 unique items, Jerry has 1 unique item and Mark has 3 unique items
Marilync1266Asked:
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barry houdiniCommented:
Hello Marilync1266,

You can use an "array formula" like this

=SUM(IF(FREQUENCY(IF(A$2:A$100=E2,IF(B$2:B$100<>"",MATCH(B$2:B$100,B$2:B$100,0))),ROW(B$2:B$100)-ROW(B$2)+1),1))

confirmed with CTRL+SHIFT+ENTER

where E2 contains a specific name, see attached

regards, barry
27508488.xls
0

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