| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.61 | 1.86 | 1.34 |
| 2024 | 1.48 | 2.25 | 1.11 |
| 2023 | 1.94 | 2.24 | 1.64 |
| 2022 | 2.34 | 3.8 | 1.79 |
| 2021 | 2.37 | 3.41 | 1.79 |
| 2020 | 2.26 | 2.84 | 1.96 |
| 2019 | 2.59 | 3.95 | 2.13 |
| 2018 | 3.49 | 5.55 | 1.86 |
| 2017 | 7.54 | 10.49 | 5.21 |
| 2016 | 8.28 | 12.12 | 6.55 |
| 2015 | 9.73 | 16.33 | 6.17 |
| 2014 | 4.2 | 7.79 | 2.88 |
| 2013 | 5.04 | 9.29 | 3.03 |
| 2012 | 7.3 | 10.62 | 5.94 |
| 2011 | 10.13 | 13.03 | 6.09 |
| 2010 | 11.1 | 15.44 | 7.56 |
| 2009 | 7.72 | 12.39 | 3.69 |
| 2008 | 6.74 | 15.08 | 2.61 |
| 2007 | 42.63 | 109.28 | 10.36 |
| 2006 | 12.22 | 20.47 | 6.1 |
| 2005 | 8.22 | 11.74 | 5.57 |
| 2004 | 6.25 | 11.31 | 2.52 |
| 2003 | 4.03 | 4.78 | 3.37 |
| 2002 | 6.98 | 8.69 | 4.89 |
| 2001 | 9.03 | 12.21 | 5.88 |
| 2000 | 6.11 | 10.04 | 3.78 |
| 1999 | 4.4 | 5.83 | 3.31 |
| 1998 | 5.8 | 7.87 | 3.96 |
| 1997 | 4.14 | 7.4 | 2.54 |