title: Get Exact Number of Days Between Certain Months Using DATEDIFF() Not Giving Expected Results
body: <p>The following is sample data:</p>
  
  <pre><code>NewReportDate | Age      | OldReportDate
  -----------------------------------------
  2014-04-28    |31.558767 | 2014-03-28
  2014-04-28    |13-438767 | 2014-03-28
  2014-04-28    |13.198767 | 2014-03-28
  </code></pre>
  
  <p>The following is my query:</p>
  
  <pre><code>SELECT 
  Q.Type
  ,Q.Oper
  ,Q.SNo
  ,Q.Hours
  ,CONVERT(Date, Q.ReportDate + '28', 112) AS 'Report_Date'
  , a.*
  , (DATEDIFF(dy, CONVERT(Date, Q.ReportDate + '28', 112),A.ReportDate )/365) + A.age AS 'AdjustedAge'
  FROM QReport Q
  INNER JOIN AReport a
  ON q.name = a.name 
  WHERE a.ReportDate = '2014-03-28 00:00:00.000'
  ORDER BY A.ReportDate desc
  </code></pre>
  
  <p>The following are my results:</p>
  
  <pre><code>NewReportDate | Age      | OldReportDate | AdjustedAge|
  -------------------------------------------------------
  2014-04-28    |31.558767 | 2014-03-28    |31.558767 
  2014-04-28    |13.438767 | 2014-03-28    |13.438767
  2014-04-28    |13.198767 | 2014-03-28    |13.198767 
  </code></pre>
  
  <p>Why is my <code>AdjustedAge</code> not changing when there is a month difference between <code>NewReportDate</code> and <code>OldReportDate</code>?</p>
  
  <p>There should be a difference in the decimal.</p>