| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.3 | 2.88 | 1.96 |
| 2024 | 2.03 | 2.97 | 1.53 |
| 2023 | 2.68 | 3.48 | 2.42 |
| 2022 | 2.62 | 3.61 | 2.08 |
| 2021 | 2.17 | 2.89 | 1.8 |
| 2020 | 2.48 | 2.96 | 2.31 |
| 2019 | 2.93 | 4.18 | 2.12 |
| 2018 | 2.99 | 5.26 | 1.77 |
| 2017 | 6.48 | 9.43 | 3.58 |
| 2016 | 5.32 | 6.86 | 4.05 |
| 2015 | 6.08 | 8.94 | 3.13 |
| 2014 | 2.56 | 3.65 | 1.94 |
| 2013 | 2.38 | 3.2 | 1.85 |
| 2012 | 2.22 | 2.75 | 1.87 |
| 2011 | 3.4 | 4.56 | 2.11 |
| 2010 | 5.58 | 7.79 | 4.08 |
| 2009 | 5.54 | 6.59 | 4.17 |
| 2008 | 6.36 | 13.46 | 2.44 |
| 2007 | 7.59 | 10.81 | 3.82 |
| 2006 | 4.92 | 6.93 | 3.22 |
| 2005 | 4.59 | 5.29 | 3.94 |
| 2004 | 4.57 | 5.36 | 3.46 |
| 2003 | 4.14 | 4.82 | 3.57 |
| 2002 | 5.84 | 7.14 | 4.75 |
| 2001 | 10.36 | 12.25 | 6.69 |
| 2000 | 7.54 | 12.4 | 4.66 |