| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.87 | 0.93 | 0.77 |
| 2024 | 0.89 | 1.18 | 0.7 |
| 2023 | 1.2 | 1.59 | 0.9 |
| 2022 | 1.16 | 1.66 | 0.79 |
| 2021 | 0.79 | 1.49 | 0.62 |
| 2020 | 0.79 | 1.02 | 0.66 |
| 2019 | 1.05 | 1.6 | 0.78 |
| 2018 | 1.29 | 1.62 | 0.77 |
| 2017 | 1.78 | 2.14 | 1.44 |
| 2016 | 1.93 | 2.67 | 1.28 |
| 2015 | 2.94 | 4.53 | 1.6 |
| 2014 | 2.54 | 3.81 | 1.87 |
| 2013 | 2.5 | 3.22 | 1.98 |
| 2012 | 2.8 | 4.49 | 1.79 |
| 2011 | 14.63 | 36.08 | 3.23 |
| 2010 | 10.94 | 20.6 | 5.09 |
| 2009 | 4.6 | 5.86 | 3.28 |
| 2008 | 5.48 | 11.68 | 2.53 |
| 2007 | 5.46 | 9.67 | 2.09 |
| 2006 | 2.31 | 3.28 | 1.62 |
| 2005 | 1.57 | 1.85 | 1.25 |
| 2004 | 2.28 | 3.44 | 1.4 |
| 2003 | 3.37 | 3.89 | 2.48 |
| 2002 | 5.11 | 5.55 | 4.84 |