title: Find and gzip files in subdirectories
body: <p>I have *.xls files in the location /home/Docs/Calc. There are multiple subdirectories inside that folder. Eg</p>
  
  <pre><code>/home/Docs/Calc/2011
  /home/Docs/Calc/2012
  /home/Docs/Calc/2013
  </code></pre>
  
  <p>I can gzip each file under the subdirectories using the find command, </p>
  
  <pre><code>find /home/Docs/Calc -iname "*.xls" -exec gzip {} \;
  </code></pre>
  
  <p>but how can I gzip all the files in each subdirectory ? eg.</p>
  
  <pre><code>/home/Docs/Calc/2011/2011.tar.gz
  /home/Docs/Calc/2012/2012.tar.gz
  /home/Docs/Calc/2013/2013.tar.gz
  </code></pre>
  
  <p>I must add that /home/Docs/Calc is one of the many folders eg Calc-work, calc-tax, calc-bills. All of these have the year subfolders in them</p>