| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.64 | 0.88 | 0.45 |
| 2024 | 0.52 | 0.77 | 0.4 |
| 2023 | 0.58 | 0.65 | 0.51 |
| 2022 | 0.67 | 0.87 | 0.47 |
| 2021 | 0.97 | 1.59 | 0.69 |
| 2020 | 0.58 | 1.56 | 0.45 |
| 2019 | 0.52 | 0.75 | 0.34 |
| 2018 | 0.52 | 0.86 | 0.32 |
| 2017 | 1.31 | 2.07 | 0.8 |
| 2016 | 1.99 | 2.77 | 1.55 |
| 2015 | 3.61 | 6.96 | 2.31 |
| 2014 | 1.33 | 2.42 | 0.98 |
| 2013 | 0.84 | 1.24 | 0.63 |
| 2012 | 0.7 | 0.87 | 0.56 |
| 2011 | 0.98 | 1.27 | 0.64 |
| 2010 | 6.51 | 15.46 | 0.96 |
| 2009 | 10.38 | 18.32 | 4.09 |
| 2008 | 4.97 | 9.19 | 2.58 |
| 2007 | 3.23 | 4.84 | 1.78 |
| 2006 | 2 | 2.68 | 1.57 |
| 2005 | 1.72 | 2.28 | 1.21 |
| 2004 | 3.1 | 6.13 | 1.69 |