| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2024 | 0 | ||
| 2023 | 0.55 | 0.76 | 0.37 |
| 2022 | 0.99 | 1.4 | 0.65 |
| 2021 | 2 | 2.66 | 1.32 |
| 2020 | 6.72 | 16.31 | 2.66 |
| 2019 | 31.56 | 54.09 | 11.33 |
| 2018 | 18.3 | 29.63 | 11.31 |
| 2017 | 54.05 | 142.46 | 18.94 |
| 2016 | 128.29 | 328.06 | 22.79 |
| 2015 | 27.28 | 45.15 | 17.78 |
| 2014 | 16.13 | 20.61 | 13.43 |
| 2013 | 15.44 | 18.16 | 11.98 |
| 2012 | 18.15 | 24.24 | 14.57 |
| 2011 | 31.56 | 46.44 | 17.14 |
| 2010 | 32.54 | 55.55 | 21.96 |
| 2009 | 24.52 | 34.79 | 14.97 |
| 2008 | 46.02 | 97.84 | 6.59 |
| 2007 | 44.63 | 128.16 | 5.35 |
| 2006 | 3.78 | 5.97 | 2.47 |
| 2005 | 2.29 | 2.96 | 1.57 |
| 2004 | 2.61 | 4.65 | 1.73 |