| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0 | ||
| 2024 | 0 | ||
| 2023 | 0 | ||
| 2022 | 0 | ||
| 2021 | 0 | ||
| 2020 | 0 | ||
| 2019 | 0 | ||
| 2018 | 5.31 | 8.51 | 3.53 |
| 2017 | 7.64 | 11.81 | 4.99 |
| 2016 | 12.06 | 15.57 | 8.87 |
| 2015 | 8.14 | 17.48 | 3.37 |
| 2014 | 4.56 | 5.84 | 2.39 |
| 2013 | 2.57 | 3.22 | 2.1 |
| 2012 | 2.65 | 3.4 | 1.95 |
| 2011 | 2.83 | 3.45 | 2.2 |
| 2010 | 3.31 | 4.42 | 2.31 |
| 2009 | 2.52 | 3.52 | 1.48 |
| 2008 | 3.46 | 5.96 | 0.95 |
| 2007 | 4.7 | 7.13 | 3.32 |
| 2006 | 3.66 | 4.67 | 2.51 |
| 2005 | 1.91 | 3.27 | 1.04 |
| 2004 | 2.97 | 4.99 | 1.81 |
| 2003 | 4.47 | 5.28 | 3.27 |
| 2002 | 6.31 | 7.09 | 5.52 |
| 2001 | 6.7 | 8.32 | 5.37 |
| 2000 | 6.01 | 9.3 | 4.45 |
| 1999 | 4.09 | 5.58 | 2.65 |
| 1998 | 3.31 | 5.06 | 2.49 |
| 1997 | 3.03 | 4.21 | 2.1 |