| Month | Change |
|---|---|
| 4/10 | -2.46 |
| 5/10 | -2.37 |
| 6/10 | -2.28 |
| 7/10 | -1.73 |
| 8/10 | -2.56 |
| 9/10 | -2.07 |
| Month | Change | 4/11 | -1.80 |
| 5/11 | -2.36 |
| 6/11 | -1.77 |
| Month | Change | 4/12 | -1.91 |
| 5/12 | -2.73 |
| 6/12 | -2.18 |
| 7/12 | -2.47 |
| 8/12 | -2.90 |
| 9/12 | -3.00 |
| 10/12 | -2.75 |
| Month | Change | 4/13 | -2.13 |
| 5/13 | -1.80 |
| 6/13 | -1.79 |
| 9/13 | -1.44 |
| 10/13 | -2.56 |
| Month | Change | 4/14 | -2.23 |
| 5/14 | -1.64 |
| 6/14 | -3.62 |
| 7/14 | -2.05 |
| 8/14 | -2.00 |
| 9/14 | -3.10 |
| Month | Change | 4/15 | -7.08 |
| 5/15 | -6.09 |
| 6/15 | -6.64 |
| 7/15 | -6.73 |