Hi Marsha,

One way

=SUMPRODUCT((A1:A200<>"")/COUNTIF(A1:A200,A1:A200&""))

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HTH

RP
(remove nothere from the email address if mailing direct)


"Marsha" <Marsha@discussions.microsoft.com> wrote in message
news:E362D9A0-8A06-43E4-81DD-0B2F28C6C18E@microsoft.com...
> I need to be able to count information based on approximately 350 social
> security numbers, exlcuding duplicates. Any ideas on the formula? Thanks
so
> much,
> Marsha