With supplier No and date in A2:B9 and result date in D2 enter this
array formula in E2 (ctrl+shift+enter to execute) and fill down:

=COUNT(1/FREQUENCY(IF(B$2:B$9=D2,A$2:A$9),A$2:A$9))

On Feb 9, 11:56 am, Nelson wrote:
Hi!

How can I count the unique numbers in a range where I have numbers, blank
cells and text, everytime a condition is met?
It's like this:

Source page

Supplier Nº Date
28000 01-01-2007
28001 01-01-2007
jtrjkfff 01-01-2007
28000 01-01-2007
28001 02-01-2007
(blank) 02-01-2007
ddfgdr 02-01-2007
28001 02-01-2007

Results page

Date Count of Suppliers
01-01-2007 2
02-01-2007 1
...

Thanks a lot!