| Month | Change |
|---|---|
| 4/11 | -5.33 |
| 5/11 | -4.69 |
| 6/11 | -5.58 |
| 7/11 | -5.81 |
| 8/11 | -5.90 |
| 9/11 | -5.12 |
| Month | Change | 4/12 | -4.19 |
| 5/12 | -4.91 |
| 6/12 | -4.84 |
| 7/12 | -4.87 |
| 8/12 | -5.27 |
| 9/12 | -5.50 |
| 10/12 | -5.08 |
| Month | Change | 4/13 | -5.48 |
| 5/13 | -5.64 |
| 6/13 | -6.39 |
| 7/13 | -6.16 |
| 8/13 | -5.79 |
| 9/13 | -6.55 |
| 10/13 | -6.07 |