| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.13 | 5.33 | 3.62 |
| 2024 | 3.08 | 4.38 | 1.93 |
| 2023 | 3.58 | 4.15 | 3.22 |
| 2022 | 4.77 | 7.1 | 3.22 |
| 2021 | 3.82 | 6.36 | 2.14 |
| 2020 | 2.6 | 3.22 | 2.19 |
| 2019 | 2.94 | 3.74 | 2.39 |
| 2018 | 3.43 | 4.52 | 2.59 |
| 2017 | 5.92 | 7.59 | 4.26 |
| 2016 | 7.13 | 10.3 | 5.21 |
| 2015 | 7.09 | 11.98 | 3.39 |
| 2014 | 5.49 | 7 | 4.29 |
| 2013 | 5.64 | 7.64 | 4.14 |
| 2012 | 9.39 | 12.3 | 6.05 |
| 2011 | 12.42 | 18.94 | 7.8 |
| 2010 | 17.3 | 57.04 | 5.75 |
| 2009 | 24.15 | 61.02 | 4.6 |
| 2008 | 8.1 | 18.69 | 3.55 |
| 2007 | 9.54 | 15.39 | 3.58 |
| 2006 | 4.09 | 5.69 | 2.95 |
| 2005 | 2.89 | 4.43 | 1.95 |
| 2004 | 5.23 | 8.71 | 2.92 |
| 2003 | 9.41 | 11.96 | 7.39 |
| 2002 | 7.51 | 8.53 | 6.39 |
| 2001 | 9.26 | 11.49 | 6.9 |
| 2000 | 7.78 | 11.08 | 4.31 |
| 1999 | 4.64 | 5.76 | 3.71 |
| 1998 | 4.48 | 6.39 | 3.44 |
| 1997 | 4.69 | 6.28 | 3.58 |