| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2019 | 16.64 | 19.9 | 14.06 |
| 2018 | 15.07 | 19.41 | 11.61 |
| 2017 | 21.91 | 25.65 | 18.57 |
| 2016 | 22.91 | 26.67 | 20.38 |
| 2015 | 28.41 | 41.45 | 18.51 |
| 2014 | 18.94 | 29.68 | 13.3 |
| 2013 | 54.98 | 82.13 | 21.45 |
| 2012 | 49.70 | 58.78 | 35.27 |
| 2011 | 38.20 | 51.51 | 27.47 |
| 2010 | 47.11 | 73.53 | 32.77 |
| 2009 | 50.86 | 71.57 | 36.49 |
| 2008 | 45.36 | 72.83 | 25.48 |
| 2007 | 53.66 | 74.96 | 26.72 |
| 2006 | 38.06 | 65.73 | 22.75 |
| 2005 | 56.44 | 80.17 | 41.97 |
| 2004 | 76.96 | 110.46 | 57.47 |
| 2003 | 49.31 | 65.22 | 42.19 |
| 2002 | 36.88 | 41.61 | 30.74 |
| 2001 | 38.48 | 44.78 | 30.36 |
| 2000 | 31.03 | 36.35 | 24.12 |
| 1999 | 28.27 | 34.06 | 22.27 |