Learn how to count the number of unique and distinct values in a column based on data in another column using array in Microsof Excel.

Specifying the conditional count of a value sounds like a daunting task, but two Excel functions make quick work of this challenge.

Now, let’s look at a simple example. Specifically, let’s use Subtotal to return a count of the number of books due back on each date in the Due column in the sheet below.

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.