title: Calculating bi-weekly development of tickets in dax
body: <p>I need some help. My data set looks currently like this:</p>
  <pre><code>Date    Ticket (1/0)        Week number
  01.07.2020       0      1
  01.07.2020       1      1
  01.07.2020       1      1
  01.07.2020       0      1
  15.07.2020       0      2
  15.07.2020       0      2
  15.07.2020       0      2
  01.08.2020       1      3
  01.08.2020       1      3
  01.08.2020       0      3
  01.08.2020       0      3
  01.08.2020       1      3
  </code></pre>
  <p>The end result that I need should be something like this:</p>
  <pre><code>Date                  01.07.2020    15.07.2020      01.08.2020
  Development of tickets     2          -2                1
  </code></pre>
  <p>I need the end matrix to sum the tickets in that week and substract the tickets of the previous week from it. How do I achieve that? How should the measure look like?</p>
  <p>Thanks for the help!</p>