| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.92 | 5.65 | 4.16 |
| 2024 | 4.22 | 7.39 | 2.82 |
| 2023 | 4.43 | 5.77 | 3.78 |
| 2022 | 4.05 | 4.8 | 3.29 |
| 2021 | 4.18 | 4.75 | 3.62 |
| 2020 | 3.72 | 5.09 | 3.11 |
| 2019 | 3.36 | 4.26 | 2.3 |
| 2018 | 2.83 | 4.19 | 1.82 |
| 2017 | 4.78 | 6.09 | 3.5 |
| 2016 | 5.41 | 7.39 | 4.53 |
| 2015 | 10.4 | 19.09 | 6.32 |
| 2014 | 6.31 | 11.78 | 4.16 |
| 2013 | 3.56 | 4.81 | 2.24 |
| 2012 | 4.12 | 6.63 | 2.01 |
| 2011 | 5.21 | 7.05 | 3.41 |
| 2010 | 8.69 | 12.8 | 6.43 |
| 2009 | 8.2 | 12.63 | 3.55 |
| 2008 | 6.23 | 15.57 | 2.71 |
| 2007 | 8.73 | 14.35 | 1.41 |
| 2006 | 1.39 | 1.64 | 1.16 |
| 2005 | 1.37 | 1.68 | 1.1 |
| 2004 | 2.07 | 2.86 | 1.54 |
| 2003 | 2.87 | 3.88 | 2.08 |
| 2002 | 3.93 | 4.52 | 2.9 |
| 2001 | 5.72 | 7.21 | 4.25 |
| 2000 | 7.1 | 8.68 | 5.09 |
| 1999 | 4.7 | 6.38 | 2.7 |
| 1998 | 4.02 | 5.17 | 2.76 |