| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.68 | 2.57 | 1.42 |
| 2024 | 1.74 | 2.74 | 1.34 |
| 2023 | 4.39 | 6.32 | 2.11 |
| 2022 | 4.51 | 6.15 | 2.84 |
| 2021 | 2.45 | 3.62 | 1.36 |
| 2020 | 0.94 | 1.77 | 0.5 |
| 2019 | 0.72 | 0.87 | 0.59 |
| 2018 | 1.01 | 1.59 | 0.62 |
| 2017 | 8.16 | 32.68 | 1.54 |
| 2016 | 12.85 | 19.51 | 9.7 |
| 2015 | 15.65 | 27.61 | 9.97 |
| 2014 | 7.35 | 12.65 | 4.72 |
| 2013 | 5.09 | 5.89 | 4.04 |
| 2012 | 6.02 | 7.95 | 4.51 |
| 2011 | 9.8 | 12.93 | 5.28 |
| 2010 | 13.08 | 17.83 | 9.37 |
| 2009 | 7.44 | 10.73 | 3.75 |
| 2008 | 4.54 | 8.62 | 1.98 |
| 2007 | 6.96 | 10.4 | 3.06 |
| 2006 | 2.86 | 3.4 | 2.19 |
| 2005 | 2.77 | 3.6 | 2.11 |
| 2004 | 4.9 | 8.59 | 3.11 |