| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.22 | 0.3 | 0.16 |
| 2024 | 0.15 | 0.2 | 0.12 |
| 2023 | 0.16 | 0.21 | 0.12 |
| 2022 | 0.1 | 0.14 | 0.07 |
| 2021 | 0.12 | 0.17 | 0.09 |
| 2020 | 0.19 | 0.27 | 0.14 |
| 2019 | 0.11 | 0.16 | 0.09 |
| 2018 | 0.18 | 0.25 | 0.11 |
| 2017 | 0.36 | 0.67 | 0.21 |
| 2016 | 21.97 | 47.99 | 0.61 |
| 2015 | 8.5 | 21.54 | 4.15 |
| 2014 | 3.76 | 5.22 | 2.73 |
| 2013 | 3.16 | 3.61 | 2.72 |
| 2012 | 3.84 | 5.2 | 2.73 |
| 2011 | 6.6 | 9.54 | 3.13 |
| 2010 | 8.8 | 10.3 | 6.96 |
| 2009 | 6.32 | 9.65 | 2.27 |
| 2008 | 6.23 | 11.52 | 1.56 |
| 2007 | 7.25 | 12.47 | 2 |
| 2006 | 1.53 | 2.27 | 1.01 |
| 2005 | 1.15 | 2.01 | 0.48 |
| 2004 | 1.44 | 2.53 | 0.85 |