title: How to apply grouped result to VAR.S?
body: <p>I'm new to DAX. I want to create a measure that groups the <code>Date</code> table by the same date, counts the numbers (result is like below <code>Count</code> table) and calculates the variance of counts.</p>
  
  <p><a href="https://i.stack.imgur.com/yKqsM.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/yKqsM.png" alt="example"></a></p>
  
  <p>With the help of <a href="https://stackoverflow.com/questions/46084978/dax-expression-for-count-of-groupby">another question</a>, I am able to write the following DAX so as to transform <code>Date</code> table into <code>Count</code> table, but I can't figure out how <code>VAR.S</code> can be used with it. Can you help me? Thanks!</p>
  
  <pre><code>SUMMARIZECOLUMNS(Dates[Date], "DateCount", COUNT(Dates[Date]))
  </code></pre>