| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.15 | 0.2 | 0.09 |
| 2024 | 0.2 | 0.27 | 0.14 |
| 2023 | 0.39 | 0.81 | 0.19 |
| 2022 | 0.66 | 1.66 | 0.43 |
| 2021 | 0.33 | 0.48 | 0.24 |
| 2020 | 0.32 | 0.57 | 0.24 |
| 2019 | 0.44 | 0.66 | 0.35 |
| 2018 | 0.91 | 2.07 | 0.36 |
| 2017 | 1.46 | 2.94 | 0.81 |
| 2016 | 4.4 | 10 | 2.08 |
| 2015 | 6.75 | 9.95 | 3.34 |
| 2014 | 3.31 | 4.87 | 1.64 |
| 2013 | 2.94 | 5.44 | 1.72 |
| 2012 | 5.19 | 7.51 | 3.7 |
| 2011 | 7.92 | 12.56 | 4.9 |
| 2010 | 35.56 | 67.01 | 11.85 |
| 2009 | 615.69 | 3083.62 | 57.83 |
| 2008 | 543.17 | 2149.6 | 333.68 |
| 2007 | 625.94 | 1011.76 | 430.51 |
| 2006 | 20.2 | 26.17 | 17.64 |
| 2005 | 4.51 | 20.22 | 0.15 |
| 2004 | 0.8 | 2.28 | 0.27 |