title: MDX return fiscal PriorMTD date as value
body: <p>I am trying to create MDX Calculated member which returns prior mtd date.</p>
  
  <p>This is Calculated member I've created:</p>
  
  <pre><code>CREATE MEMBER CURRENTCUBE.[Measures].PriorMTDDate
   AS cousin(
              [Date].[Fiscal].CurrentMember,
              [Date].[Fiscal].CurrentMember.parent.parent.lag(1)
          ), 
  VISIBLE = 1  ;   
  </code></pre>
  
  <p>And this is query, but it returns just null:</p>
  
  <pre><code>select {[Measures].[PriorMTDDate]} on 0
  from [WH_Cube]
  WHERE ( [Date].[Fiscal].[Date].&amp;[2014-09-12T00:00:00] )
  </code></pre>
  
  <p>Any idea what am I doing wrong?</p>
  
  <p><strong>EDIT: Another example returning null:</strong></p>
  
  <pre><code>WITH MEMBER Measures.x AS  
      [Date].[Fiscal].CurrentMember 
  SELECT Measures.x ON 0
  FROM [WH_Cube]
  WHERE ( [Date].[Fiscal].[Date].&amp;[2014-09-30T00:00:00] )
  </code></pre>