title: R Select latest date row for each individual
body: <p>I have a dataframe in R with values such as:</p>
  <pre><code>    Individual     Date            Score
        A          2019/07/01         10
        A          2019/06/01         5
        B          2019/06/01         8
        C          2019/08/01         8
        C          2019/06/01         5
  </code></pre>
  <p>I want to filter to have just the latest score for each individual.</p>
  <pre><code>    Individual     Date            Score
        A          2019/07/01         10
        B          2019/06/01         8
        C          2019/08/01         8
  </code></pre>
  <p>I'm not sure the most efficient way of achieving this.</p>
  <p>Thank you for any help</p>