| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.86 | 3.53 | 2.31 |
| 2024 | 6.02 | 12.79 | 2.75 |
| 2023 | 10.83 | 17.99 | 6.86 |
| 2022 | 6.75 | 8.88 | 4.7 |
| 2021 | 8.22 | 14.06 | 5 |
| 2020 | 11.1 | 15.79 | 7.7 |
| 2019 | 8.36 | 10 | 6.2 |
| 2018 | 6.62 | 7.85 | 5.31 |
| 2017 | 5.27 | 6.95 | 4.07 |
| 2016 | 4.23 | 5.2 | 3.4 |
| 2015 | 5.71 | 7.35 | 3.77 |
| 2014 | 3.84 | 4.85 | 3.34 |
| 2013 | 3.22 | 4.64 | 1.84 |
| 2012 | 2.03 | 2.63 | 1.63 |
| 2011 | 3.06 | 4.05 | 1.83 |
| 2010 | 4.18 | 5.34 | 3.03 |
| 2009 | 4.43 | 6.22 | 1.55 |
| 2008 | 2.48 | 4.3 | 1.27 |
| 2007 | 3.55 | 5.62 | 1.55 |
| 2006 | 1.5 | 2.04 | 0.86 |
| 2005 | 0.97 | 1.3 | 0.75 |
| 2004 | 1.57 | 2.05 | 1.22 |
| 2003 | 1.84 | 2.34 | 1.49 |
| 2002 | 2.53 | 3.04 | 1.84 |
| 2001 | 3.2 | 3.87 | 2.31 |
| 2000 | 3.19 | 3.62 | 2.49 |
| 1999 | 2.45 | 3.89 | 1.81 |
| 1998 | 2.56 | 3.32 | 1.96 |
| 1997 | 2.92 | 4.34 | 2.02 |