title: Return first date equal to or older than given date?
body: <p>I'm trying to get a single value from a <code>pd.DataFrame</code> by using the following lines:</p>
  
  <pre><code>end = datetime.datetime.strptime('2016-03-01', '%Y-%m-%d')
  
  timeranges = [(end - datetime.timedelta(30)),
                (end - datetime.timedelta(60)),
                (end - datetime.timedelta(365))]
  
  nav_df = data[(data['Symbol'] == 'account') &amp; (data['Type'] == 'nav')
                 &amp; (data['Date'] &gt;= date)]
  </code></pre>
  
  <p>How do I tell pandas to limit the returning value to the first date that evaluates to <code>True</code> in <code>data['Date'] &gt;= date</code> ?</p>
  
  <p><strong>Sample Data:</strong></p>
  
  <p><a href="http://pastebin.com/1pRatDts" rel="nofollow">http://pastebin.com/1pRatDts</a></p>