title: Reversing the order of values in a single column of a Dataframe
body: <p>I was just wondering how to reverse the order of the values only in the Column <code>Date</code> in the dataframe <code>df</code> below, so that 2015-06-18 will be in the last row of <code>Date</code>. I've unfortunately only been able to find posts on how to change the order of all the columns in a dataframe. </p>
  
  <pre><code>       Date             YEAR  SHARE-VALUE  Cusip
  0      2015-06-18         1    0.3293      APPL
  1      2015-06-17         1    0.3528      GOOGL
  2      2015-06-16         1    0.3507      LEN
  3      2015-06-15         1    0.3581      TSD
  </code></pre>