| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0 | ||
| 2024 | 0 | ||
| 2023 | 0.7 | 1 | 0.36 |
| 2022 | 1.37 | 2.67 | 0.83 |
| 2021 | 2.06 | 3.55 | 1.09 |
| 2020 | 1.93 | 2.47 | 1.46 |
| 2019 | 2.69 | 3.95 | 1.7 |
| 2018 | 5.38 | 7.69 | 2.65 |
| 2017 | 8.29 | 11.18 | 6.48 |
| 2016 | 13.36 | 22.45 | 10.6 |
| 2015 | 46.37 | 149.67 | 6.35 |
| 2014 | 13.76 | 48.16 | 3.13 |
| 2013 | 20.93 | 34.45 | 10.81 |
| 2012 | 13.2 | 20.85 | 9.72 |
| 2011 | 18.04 | 24.25 | 10.51 |
| 2010 | 7.21 | 13.91 | 3.75 |
| 2009 | 4.29 | 5.93 | 2.99 |
| 2008 | 13.6 | 42.12 | 2.47 |
| 2007 | 23.77 | 50.12 | 5.25 |
| 2006 | 2.87 | 5.27 | 1.47 |
| 2005 | 1.7 | 2.2 | 1.18 |
| 2004 | 4.71 | 13.88 | 1.81 |