| Month | Change |
|---|---|
| 4/11 | -27.99 |
| 5/11 | -28.34 |
| 6/11 | -28.09 |
| 7/11 | -27.47 |
| 8/11 | -26.09 |
| 9/11 | -28.47 |
| Month | Change | 4/12 | -27.46 |
| 5/12 | -27.95 |
| 6/12 | -26.34 |
| 7/12 | -24.94 |
| 8/12 | -26.57 |
| 9/12 | -25.64 |
| 10/12 | -26.29 |
| Month | Change | 4/13 | -25.36 |
| 5/13 | -25.56 |
| 6/13 | -26.78 |
| 7/13 | -24.10 |
| 8/13 | -24.94 |
| 9/13 | -24.89 |
| 10/13 | -24.93 |