| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.53 | 3.93 | 3.18 |
| 2024 | 3.69 | 4.44 | 2.88 |
| 2023 | 2.96 | 3.62 | 2.68 |
| 2022 | 2.7 | 3.71 | 2.17 |
| 2021 | 2.41 | 3.4 | 1.98 |
| 2020 | 2.55 | 3.39 | 2.14 |
| 2019 | 2.38 | 2.88 | 1.94 |
| 2018 | 2.75 | 3.66 | 1.96 |
| 2017 | 4.52 | 5.76 | 3.23 |
| 2016 | 5.56 | 6.42 | 4.73 |
| 2015 | 6.96 | 10.54 | 5.45 |
| 2014 | 5.41 | 6.82 | 4.41 |
| 2013 | 5.32 | 6.77 | 3.99 |
| 2012 | 4.24 | 4.93 | 3.5 |
| 2011 | 5.7 | 6.89 | 4.11 |
| 2010 | 5.68 | 7.61 | 3.84 |
| 2009 | 3.85 | 5.71 | 2.63 |
| 2008 | 3.59 | 7.68 | 1.67 |
| 2007 | 4.75 | 8.31 | 1.52 |
| 2006 | 1.39 | 1.6 | 1.06 |
| 2005 | 1.32 | 1.59 | 1.01 |
| 2004 | 2.06 | 3.11 | 1.36 |