| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.77 | 4.62 | 3.24 |
| 2024 | 3.29 | 5.45 | 2.1 |
| 2023 | 3.78 | 4.97 | 3.02 |
| 2022 | 4.56 | 6.83 | 3.19 |
| 2021 | 4.96 | 11.24 | 2.31 |
| 2020 | 2.74 | 3.75 | 2.09 |
| 2019 | 2.4 | 3.09 | 1.77 |
| 2018 | 3.12 | 4.67 | 1.81 |
| 2017 | 4.68 | 5.65 | 3.84 |
| 2016 | 5.77 | 7.89 | 4.94 |
| 2015 | 5.83 | 11.51 | 3.08 |
| 2014 | 3.57 | 4.88 | 2.67 |
| 2013 | 2.82 | 5.11 | 1.66 |
| 2012 | 2.41 | 3.13 | 1.43 |
| 2011 | 4.36 | 6.59 | 2.58 |
| 2010 | 7.35 | 9.3 | 5.31 |
| 2009 | 3.77 | 7.43 | 2.11 |
| 2008 | 4.52 | 11.59 | 1.64 |
| 2007 | 20.91 | 36.34 | 8.18 |
| 2006 | 5.07 | 10.4 | 2.56 |
| 2005 | 2.77 | 4.32 | 1.92 |
| 2004 | 4.14 | 5.72 | 3.24 |
| 2003 | 4.98 | 6.22 | 3.73 |
| 2002 | 6.46 | 7.13 | 5.71 |
| 2001 | 6.36 | 8.15 | 4.94 |
| 2000 | 6.73 | 9 | 4.06 |
| 1999 | 5.01 | 6.87 | 3.58 |
| 1998 | 4.05 | 5.08 | 2.79 |