| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2020 | 8.02 | 8.84 | 6.97 |
| 2019 | 7.45 | 8.93 | 6.08 |
| 2018 | 9.77 | 16.63 | 6.06 |
| 2017 | 18.87 | 37.09 | 11.27 |
| 2016 | 56.67 | 96.74 | 20.98 |
| 2015 | 21.99 | 32.81 | 14.62 |
| 2014 | 13.31 | 19.03 | 10.9 |
| 2013 | 10.21 | 17.26 | 5.91 |
| 2012 | 10.52 | 16.17 | 6.38 |
| 2011 | 9.34 | 10.94 | 7.5 |
| 2010 | 11.56 | 24.36 | 8.57 |
| 2009 | 33.85 | 77.28 | 5.88 |
| 2008 | 12.74 | 23.5 | 5.16 |
| 2007 | 16.26 | 22.86 | 12.28 |
| 2006 | 7.25 | 13.41 | 5.44 |
| 2005 | 7.64 | 9.37 | 5.22 |
| 2004 | 10.69 | 14.25 | 8.23 |
| 2003 | 12.33 | 17.13 | 9.65 |
| 2002 | 22.17 | 25.29 | 18.66 |
| 2001 | 20.18 | 26.93 | 14.47 |