| 11/18/2009 | - | 18.8% | 37.6% |
| 10/28/2009 | 11/17/2009 | 18.9% | 37.8% |
| 10/21/2009 | 10/27/2009 | 17.9% | 35.8% |
| 10/14/2009 | 10/20/2009 | 16.9% | 33.8% |
| 10/07/2009 | 10/13/2009 | 16.7% | 33.4% |
| 09/30/2009 | 10/06/2009 | 16.9% | 33.8% |
| 09/23/2009 | 09/29/2009 | 17.1% | 34.2% |
| 09/16/2009 | 09/22/2009 | 17.2% | 34.4% |
| 09/09/2009 | 09/15/2009 | 17.3% | 34.6% |
| 09/02/2009 | 09/08/2009 | 17.6% | 35.2% |
| 08/26/2009 | 09/01/2009 | 17.5% | 35.0% |
| 08/19/2009 | 08/25/2009 | 17.4% | 34.8% |
| 08/12/2009 | 08/18/2009 | 17.1% | 34.2% |
| 08/05/2009 | 08/11/2009 | 16.4% | 32.8% |
| 07/29/2009 | 08/04/2009 | 16.1% | 32.2% |
| 07/22/2009 | 07/28/2009 | 15.8% | 31.6% |
| 07/15/2009 | 07/21/2009 | 16.3% | 32.6% |
| 07/08/2009 | 07/14/2009 | 16.8% | 33.6% |
| 07/01/2009 | 07/07/2009 | 16.9% | 33.8% |
| 06/24/2009 | 06/30/2009 | 17.0% | 34.0% |
| 06/17/2009 | 06/23/2009 | 16.6% | 33.2% |
| 06/10/2009 | 06/16/2009 | 15.8% | 31.6% |
| 06/03/2009 | 06/09/2009 | 14.4% | 28.8% |
| 05/27/2009 | 06/02/2009 | 13.6% | 27.2% |
| 05/20/2009 | 05/26/2009 | 13.2% | 26.4% |
| 05/13/2009 | 05/19/2009 | 13.0% | 26.0% |
| 05/06/2009 | 05/12/2009 | 12.7% | 25.4% |
| 04/29/2009 | 05/05/2009 | 12.9% | 25.8% |
| 04/01/2009 | 04/28/2009 | 13.1% | 26.2% |
| 03/25/2009 | 03/31/2009 | 11.8% | 23.6% |
| 03/18/2009 | 03/24/2009 | 11.0% | 22.0% |
| 03/11/2009 | 03/17/2009 | 11.3% | 22.6% |
| 03/04/2009 | 03/10/2009 | 11.7% | 23.4% |
| 02/25/2009 | 03/03/2009 | 12.2% | 24.4% |
| 02/18/2009 | 02/24/2009 | 12.7% | 25.4% |
| 02/11/2009 | 02/17/2009 | 13.0% | 26.0% |
| 02/04/2009 | 02/10/2009 | 13.3% | 26.6% |
| 01/28/2009 | 02/03/2009 | 13.5% | 27.0% |
| 01/21/2009 | 01/27/2009 | 13.8% | 27.6% |
| 01/14/2009 | 01/20/2009 | 14.0% | 28.0% |
| 01/07/2009 | 01/13/2009 | 13.8% | 27.6% |
| 12/31/2008 | 01/06/2009 | 14.1% | 28.2% |
| 12/24/2008 | 12/30/2008 | 14.5% | 29.0% |
| 12/17/2008 | 12/23/2008 | 15.1% | 30.2% |
| 12/10/2008 | 12/16/2008 | 16.0% | 32.0% |
| 12/03/2008 | 12/09/2008 | 17.0% | 34.0% |
| 11/26/2008 | 12/02/2008 | 17.5% | 35.0% |
| 11/20/2008 | 11/25/2008 | 18.9% | 37.8% |