| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.9 | 1.98 | 1.8 |
| 2024 | 1.89 | 2.19 | 1.57 |
| 2023 | 2.05 | 2.2 | 1.89 |
| 2022 | 2.15 | 2.6 | 1.91 |
| 2021 | 2.48 | 2.99 | 2.11 |
| 2020 | 3.41 | 4.11 | 2.76 |
| 2019 | 4.63 | 6.65 | 3.66 |
| 2018 | 6.83 | 10.68 | 4.09 |
| 2017 | 10.5 | 17.69 | 5.92 |
| 2016 | 6.13 | 7.64 | 5.28 |
| 2015 | 9.15 | 14.23 | 5.52 |
| 2014 | 6.89 | 9.11 | 5.83 |
| 2013 | 6.94 | 9.1 | 4.09 |
| 2012 | 4.71 | 5.58 | 3.62 |
| 2011 | 6.05 | 7.66 | 4.86 |
| 2010 | 7.83 | 10.14 | 6.35 |
| 2009 | 7.86 | 9.6 | 6.44 |
| 2008 | 11.59 | 20.09 | 4.54 |
| 2007 | 13.87 | 18.64 | 7.16 |
| 2006 | 7.66 | 9.65 | 6.07 |
| 2005 | 5.32 | 8.05 | 3.27 |
| 2004 | 8.88 | 13.49 | 4.88 |