title: Objective-C: Subtract 100 years from now
body: <p>How do I subtract 100 years from NSDate now?</p>
  
  <p>I have this:</p>
  
  <pre><code>NSDate *now = [NSDate date];
  NSDate *hundredYearsAgo = [now dateByAddingTimeInterval:100*365*24*60*60];
  </code></pre>
  
  <p>But this does not take into account that there are years with 365 days and years with 366 days.</p>