title: Expression in SSRS Slowing down Report Rendering
body: <p>An expression in my report is making the report to run very slowly. The expression, set in a Row Column Visibility Property is like so:</p>
  
  <pre><code>    =IIF(Parameters!View.Value = 1 AND (Fields!PastVal.Value = 0)AND(Fields!DatePay.Value = 0) AND 
      (Fields!Line.Value = 0),True, IIF(Parameters!View.Value = 2 AND Fields!TaxPaid.Value = "N",True, False))
  </code></pre>
  
  <p>Now this expression returns the right result. The problem is that it makes the report run very slow. </p>
  
  <p>To test it, I took off the expression and reports are displayed in less than 3 seconds but with the expression on, report takes over 50 seconds to run. Any help on this? Thanks.</p>