title: DAX sum different DateTime
body: <p>I have a problem here, i would like to sum the work time from my employee based on the data (time2 - time 1) daily and here is my query:</p>
  
  <pre><code>Effective Minute Work Time = 24. * 60 * (LASTNONBLANK(time2,0) -FIRSTNONBLANK(time1,0))
  </code></pre>
  
  <p>It works daily, but if i drill up to weekly / monthly data it show the wrong sum as it shown below :</p>
  
  <p><a href="https://i.stack.imgur.com/h6sjI.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/h6sjI.jpg" alt="enter image description here"></a></p>
  
  <p>What i want is summary of minute between daily different times (time2-time1)</p>
  
  <p>Thanks for your help :)</p>