| Time Period | Minimum | 25th Percentile | Median | Average | 75th Percentile | Maximum | Standard Deviation |
|---|---|---|---|---|---|---|---|
| 2004-2008 | 0.79 | 0.93 | 1.00 | 1.01 | 1.07 | 1.40 | 0.10 |
| 2009-2013 | 0.73 | 0.92 | 0.99 | 1.00 | 1.06 | 1.46 | 0.11 |
| 2014-2018 | 0.69 | 0.90 | 0.99 | 1.00 | 1.08 | 1.53 | 0.13 |
| Total | 0.69 | 0.92 | 1.00 | 1.00 | 1.07 | 1.53 | 0.12 |