title: SSRS Matrix Report With Custom Fields
body: <p>I'm trying to create a waterfall style report using the matrix style in SSRS with an unknown number of columns and they are all named m1, m2, m3, m4, etc.  Each m value contains the total paid for that time frame.  How can I specify the custom field name in the matrix.</p>
  
  <pre><code>                                    (Column_Group)
  | Date Arrived | Cost   | Payment | [ArriveDate]  |
  |---------------------------------|---------------|
  | [ArriveDate] | [Cost] | [Pay]   | [m1]          |
  </code></pre>
  
  <p>Example of what I'd like to see:</p>
  
  <pre><code>| Date Arrived | Cost   | Payment | 2018/05      | 2018/06      |
  |---------------------------------|-----------------------------|
  | 2018/05      | $200   | $100    | $25.00       | $75.00       |
  | 2018/06      | $400   | $200    | $100.00      | $100.00      |
  </code></pre>
  
  <p>SQL Dataset Sent To Report:</p>
  
  <pre><code>| ArriveDate | Cost | Pay | m1  | m2  |
  ---------------------------------------
  | 2018/05    | 200  | 100 | 25  | 50  |
  | 2018/06    | 400  | 200 | 100 | 100 |
  </code></pre>