Count the number of occurrences of Null in a column in tableau
<p>I am relatively new to Tableau and I am wondering if there is a way to calculate null values in a column.
I have a column called Email of type string and want to know how many people have not entered their email i.e. Null.</p>

<p>I tried to create a calculated field with 
count(ISNULL([Email]))</p>

<p>But this gives me the total count and not the count of null.</p>

<p>Thanks.</p>