| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.74 | 1.89 | 1.53 |
| 2024 | 1.37 | 2.79 | 1.06 |
| 2023 | 1.54 | 1.65 | 1.41 |
| 2022 | 1.62 | 1.8 | 1.44 |
| 2021 | 1.78 | 2.09 | 1.55 |
| 2020 | 1.99 | 3.13 | 1.3 |
| 2019 | 1.36 | 1.72 | 1.19 |
| 2018 | 1.67 | 3.07 | 1.2 |
| 2017 | 2.83 | 3.6 | 2.31 |
| 2016 | 3.08 | 3.59 | 2.43 |
| 2015 | 3.19 | 6.19 | 2.02 |
| 2014 | 2.36 | 3.1 | 1.89 |
| 2013 | 2.76 | 3.82 | 2.11 |
| 2012 | 2.23 | 2.7 | 1.84 |
| 2011 | 3.51 | 4.81 | 1.95 |
| 2010 | 3.7 | 5.16 | 2.7 |
| 2009 | 3.13 | 3.96 | 2.03 |
| 2008 | 3.34 | 6.23 | 1.5 |
| 2007 | 8.06 | 14.08 | 4.48 |
| 2006 | 2.51 | 4.66 | 1.53 |
| 2005 | 2.2 | 3.32 | 1.41 |
| 2004 | 3.21 | 4.73 | 2.42 |