| Time Period | Minimum | 25th Percentile | Median | Average | 75th Percentile | Maximum | Standard Deviation |
|---|---|---|---|---|---|---|---|
| 2004-2008 | 0.80 | 0.89 | 0.91 | 0.92 | 0.94 | 1.09 | 0.05 |
| 2009-2013 | 0.92 | 1.02 | 1.04 | 1.05 | 1.07 | 1.23 | 0.05 |
| 2014-2018 | 0.91 | 1.01 | 1.04 | 1.04 | 1.07 | 1.23 | 0.05 |
| Total | 0.80 | 0.94 | 1.02 | 1.00 | 1.05 | 1.23 | 0.08 |