| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2024 | 0.18 | 0.18 | 0.18 |
| 2023 | 0.55 | 1.2 | 0.18 |
| 2022 | 0.6 | 0.73 | 0.39 |
| 2021 | 0.81 | 1.25 | 0.47 |
| 2020 | 1.7 | 2.12 | 1.24 |
| 2019 | 2.09 | 3.28 | 1.49 |
| 2018 | 2.12 | 2.82 | 1.43 |
| 2017 | 2.12 | 2.76 | 1.81 |
| 2016 | 3.37 | 5.4 | 1.95 |
| 2015 | 7.38 | 11.35 | 4.32 |
| 2014 | 4.15 | 6.95 | 3.23 |
| 2013 | 6.27 | 12.23 | 3.65 |
| 2012 | 9.81 | 15.26 | 6.99 |
| 2011 | 13.84 | 23.28 | 7.27 |
| 2010 | 10 | 19.52 | 6.18 |
| 2009 | 24.73 | 44.79 | 6.42 |
| 2008 | 6.73 | 13.78 | 3.49 |
| 2007 | 30.79 | 94.7 | 6.84 |
| 2006 | 8.63 | 29.17 | 1.19 |
| 2005 | 1.1 | 1.26 | 0.87 |
| 2004 | 1.57 | 3.09 | 1.05 |