| Month | Change |
|---|---|
| 5/13 | -7.07 |
| 7/13 | -7.25 |
| 8/13 | -7.23 |
| 9/13 | -5.93 |
| Month | Change | 4/14 | -6.35 |
| 5/14 | -5.82 |
| 6/14 | -5.93 |
| 7/14 | -5.02 |
| 8/14 | -5.53 |
| 9/14 | -6.02 |
| 10/14 | -6.17 |
| Month | Change | 4/15 | -9.30 |
| 5/15 | -9.15 |
| 6/15 | -8.49 |
| 7/15 | -9.27 |
| 8/15 | -9.75 |
| 9/15 | -9.05 |
| Month | Change | 4/16 | -8.87 |
| 5/16 | -9.08 |
| 6/16 | -8.49 |
| 7/16 | -9.20 |
| 8/16 | -8.65 |
| 9/16 | -8.42 |