Work out the date 7 days ago in this format: yyyy-mm-dd
<blockquote>
  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/2708894/how-to-find-out-what-the-date-was-5-days-ago">How to find out what the date was 5 days ago?</a>  </p>
</blockquote>



<p>I'm trying to work out the date 7 days ago from today in this format: yyyy-mm-dd.</p>

<p>7 is an arbitrary number.</p>

<p>Thanks</p>
