| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2024 | 4.26 | 5 | 3.52 |
| 2023 | 4.9 | 5.96 | 4.05 |
| 2022 | 5.37 | 9.55 | 3.17 |
| 2021 | 4.91 | 5.74 | 4.37 |
| 2020 | 6.79 | 8.69 | 5.51 |
| 2019 | 8.46 | 11.39 | 7.21 |
| 2018 | 9.89 | 14.07 | 7.52 |
| 2017 | 15.07 | 18.88 | 10.77 |
| 2016 | 22.7 | 31.11 | 17.04 |
| 2015 | 17.64 | 35.92 | 3.95 |
| 2014 | 11.68 | 15.46 | 8.78 |
| 2013 | 7.92 | 11.3 | 6.71 |
| 2012 | 8.1 | 10.62 | 6.52 |
| 2011 | 11.85 | 15.9 | 7.04 |
| 2010 | 14.29 | 19.06 | 10.13 |
| 2009 | 10.59 | 17.27 | 5.48 |
| 2008 | 10.35 | 24.08 | 3.98 |
| 2007 | 17.31 | 31.03 | 3.5 |
| 2006 | 3.43 | 4.86 | 2.51 |
| 2005 | 3.08 | 3.62 | 2.2 |
| 2004 | 4.91 | 8.16 | 3.02 |
| 2003 | 6.85 | 10.29 | 5.22 |
| 2002 | 7.55 | 9.63 | 5.3 |
| 2001 | 24.55 | 42.03 | 5.8 |
| 2000 | 14.37 | 20.37 | 6.82 |
| 1999 | 5.84 | 9.38 | 3.83 |
| 1998 | 4.98 | 6.7 | 3.7 |
| 1997 | 5.33 | 6.98 | 3.34 |