| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.25 | 3.92 | 2.51 |
| 2024 | 2.85 | 4.27 | 1.84 |
| 2023 | 3.25 | 3.95 | 2.76 |
| 2022 | 3.13 | 4.31 | 2.34 |
| 2021 | 3.98 | 6.61 | 2.45 |
| 2020 | 5.53 | 8.12 | 3.31 |
| 2019 | 4.44 | 6.2 | 3.72 |
| 2018 | 5.5 | 8.62 | 2.69 |
| 2017 | 9.05 | 13.01 | 6.39 |
| 2016 | 13.2 | 15.13 | 10.26 |
| 2015 | 10.16 | 15.22 | 5.42 |
| 2014 | 4.4 | 6.35 | 3.66 |
| 2013 | 4.87 | 5.65 | 4.04 |
| 2012 | 5.57 | 7.37 | 4.61 |
| 2011 | 8.79 | 12.18 | 4.77 |
| 2010 | 9.39 | 12.38 | 6.53 |
| 2009 | 9.06 | 12.36 | 7.18 |
| 2008 | 10.94 | 19.98 | 5.46 |
| 2007 | 13.41 | 24.26 | 3.91 |
| 2006 | 3.01 | 4.03 | 1.96 |
| 2005 | 2.14 | 2.74 | 1.77 |
| 2004 | 3.32 | 4.7 | 2.3 |
| 2003 | 3.88 | 4.64 | 3.04 |
| 2002 | 2.91 | 3.32 | 2.16 |
| 2001 | 4.15 | 5.1 | 2.81 |
| 2000 | 4.77 | 5.63 | 3.89 |
| 1999 | 3.25 | 4.06 | 2.6 |
| 1998 | 3.8 | 5.51 | 2.49 |