How can I count numbers without including the repeated values?

[Guest]

Hi!

How can I count numbers without including the repeated values?
Just take a look at the situation:

John
Mary
John
Rose

The count is equal to 4 but I whant it to be 3 because "John" is repeated.
Thanks a lot!

 

[Guest]

=SUM(IF(FREQUENCY(IF(LEN(A1:A100)>0,MATCH(A1:A100,A1:A100,0),""),
IF(LEN(A1:A100)>0,MATCH(A1:A100,A1:A100,0),""))>0,1))

With your list of names in A1 to a100. Entered as an array formula ctrl +
shift + enter

 

[Dave Peterson]

One way:

=SUMPRODUCT((A1:A10<>"")/COUNTIF(A1:A10,A1:A10&""))