| Period | Index | Previous Year | Previous Month |
|---|---|---|---|
| December, 2011 | 90.7 | 1.9% | 0.2% |
| November, 2011 | 90.5 | 2.4% | 0.1% |
| October, 2011 | 90.4 | 2.4% | 0.1% |
| September, 2011 | 90.3 | 2.4% | 0.1% |
| August, 2011 | 90.2 | 2.2% | 0.1% |
| July, 2011 | 90.1 | 2.2% | 0.2% |
| June, 2011 | 89.9 | 2.0% | 0.1% |
| May, 2011 | 89.8 | 1.9% | 0.0% |
| April, 2011 | 89.8 | 1.9% | 0.0% |
| March, 2011 | 89.8 | 1.9% | 0.6% |