title: NSNumber not being retained?
body: <p>I have a variable <code>lastPostsGrabbedCounter</code>, an <code>NSNumber</code>, that is defined below.</p>
  
  <pre><code>.h
  NSNumber *lastPostsGrabbedCounter;
  @property (nonatomic, retain) NSNumber *lastPostsGrabbedCounter;
  
  .m
  @synthesize postDetailViewController, lastPostsGrabbedCounter;
  
  - (void)viewWillAppear:(BOOL)animated {
      self.lastKnownLocation = [[CLLocation alloc] init];
      self.lastPostsGrabbedCounter = [[NSNumber alloc] initWithInt:25];
   [self showActivityViewer];
  
  }
  </code></pre>
  
  <p>This .m file is a table controller in my main view. When the app is loaded this <code>viewWillAppear</code> gets called, but if I navigate to another TAB and come back and I try to use the <code>lastPostsGrabbedCounter</code> var, I it shows it as nil?</p>
  
  <p>Why isn't it retained when I navigate away? </p>