title: How to remove last row in each group if it is larger in value than the previous row?
body: <p>How would one go about removing the last row by group by column if it has a larger value than its previous column value?</p>
  
  <p>Example:</p>
  
  <pre><code>Dataframe:
  
  Column 1    Column 2
  Dog            5     
  Dog            6
  Dog            5
  Cat            3
  Cat            5
  Cat            4
  Cat            7
  Mule           2
  Mule           4
  Mule           6
  Mule           8
  Mouse          4
  Mouse          6
  Mouse          9
  
  </code></pre>
  
  <p>I would like it to appear as:</p>
  
  <pre><code>Dataframe:
  
  Column 1    Column 2
  Dog            5     
  Dog            6
  Dog            5
  Cat            3
  Cat            5
  Cat            4
  Mule           2
  Mule           4
  Mule           6
  Mouse          4
  Mouse          6
  </code></pre>
  
  <p>Only the group dog would remain the same in this situation as the last row value in column 2 for that group is smaller than its previous row.</p>