| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.32 | 3.2 | 1.93 |
| 2024 | 1.83 | 2.37 | 1.47 |
| 2023 | 2.66 | 4.1 | 1.87 |
| 2022 | 4.06 | 7.26 | 2.84 |
| 2021 | 8.56 | 12.73 | 5.99 |
| 2020 | 7.1 | 10.49 | 3.69 |
| 2019 | 3.54 | 4.56 | 2.76 |
| 2018 | 3.44 | 4.33 | 2.97 |
| 2017 | 6.93 | 12.18 | 3.86 |
| 2016 | 11.59 | 16 | 8.15 |
| 2015 | 8.41 | 13.99 | 3.1 |
| 2014 | 3.08 | 3.57 | 2.61 |
| 2013 | 3.08 | 4.49 | 2.09 |
| 2012 | 4.13 | 8.93 | 1.81 |
| 2011 | 3.29 | 5.67 | 1.83 |
| 2010 | 2.16 | 2.88 | 1.58 |
| 2009 | 1.9 | 2.73 | 0.8 |
| 2008 | 1.54 | 3.38 | 0.58 |
| 2007 | 2.17 | 3.34 | 0.98 |
| 2006 | 0.91 | 1.23 | 0.67 |
| 2005 | 0.74 | 0.93 | 0.48 |
| 2004 | 1.07 | 2.05 | 0.65 |