If you wish to count the same or duplicate values in a column only once in Excel or the count of occurances of duplicate values, read this article.

When you need to see the last value in an Excel Table or data range, these formulas will get the job done. This walk-through details the necessary formulas and some VBA code that performs the same ...

When counting unique values in Microsoft Excel, use UNIQUE() as a helper function and avoid more complicated expressions.