title: Update the new date column using the existing date column with -1 day
body: <p>I have a set of patient ids and date column. I want to update date1 column with -1 day from the date column. for example  :</p>
  
  <pre><code>ID   Date         Date1
  1   23-10-2017   23-09-2018
  1   24-09-2018   28-08-2019
  1   29-08-2019       -
  2   30-05-2016   11-06-2017
  2   12-06-2017   12-07-2018
  2   13-07-2018       -
  </code></pre>