title: Find minimum value in groups of rows
body: <p>In the SQL space (specifically T-SQL, SQL Server 2008), given this list of values:</p>
  
  <pre><code>    Status  Date
      ------  -----------------------
      ACT     2012-01-07 11:51:06.060
      ACT     2012-01-07 11:51:07.920
      ACT     2012-01-08 04:13:29.140
      NOS     2012-01-09 04:29:16.873
      ACT     2012-01-21 12:39:37.607         &lt;-- THIS
      ACT     2012-01-21 12:40:03.840
      ACT     2012-05-02 16:27:17.370
      GRAD    2012-05-19 13:30:02.503
      GRAD    2013-09-03 22:58:48.750
  </code></pre>
  
  <p>Generated from this query:</p>
  
  <pre><code>    SELECT Status, Date
      FROM Account_History
      WHERE AccountNumber = '1234'
      ORDER BY Date
  </code></pre>
  
  <p>The status for this particular object started at ACT, then changed to NOS, then back to ACT, then to GRAD. </p>
  
  <p>What is the best way to get the minimum date from the latest "group" of records where Status = 'ACT'?</p>