title: How to combine the date in different columns? (Tableau)
body: <p>I have a dataset ab the donor of the organization. Each row starts with donor's ID and name, home address, donate_date_1, donate_amount_1, donate_date_2, donate_amount_2, keep going until 98. It looks similar to this</p>
  <pre><code>Donor_ID   NAME   donate_date_1   donate_amount_1   donate_date_2   donate_amount_2  Total_Amount
  0           A     Month/Day/Year        100         Month/Day/Year        200            300
  1           B     Month/Day/Year        200         Month/Day/Year         50            250
  2           C     Month/Day/Year       1000         Month/Day/Year        500           1500
  </code></pre>
  <p>The dataset has the donors' records from 1982. Every donor starts to donate on different date, ex: 2007 to donor1 is the first donation, but to donor 2 might be the 10th donation.</p>
  <p>So here is my question: How can I combine all the dates to see which year the donors donate the most money and create the filter to see how much money was donated in total in the specific period?</p>