| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.66 | 0.71 | 0.62 |
| 2024 | 0.67 | 0.74 | 0.57 |
| 2023 | 0.81 | 1.03 | 0.65 |
| 2022 | 0.79 | 0.92 | 0.69 |
| 2021 | 0.87 | 1.08 | 0.76 |
| 2020 | 1.17 | 1.49 | 0.97 |
| 2019 | 1.53 | 1.98 | 1.32 |
| 2018 | 1.62 | 1.99 | 1.36 |
| 2017 | 3.02 | 6.47 | 1.8 |
| 2016 | 2.99 | 3.7 | 2.34 |
| 2015 | 3.99 | 6.51 | 2.27 |
| 2014 | 1.43 | 3.78 | 1.08 |
| 2013 | 1.53 | 1.97 | 1.22 |
| 2012 | 1.71 | 2.34 | 1.32 |
| 2011 | 2.43 | 3.83 | 1.35 |
| 2010 | 3.46 | 4.8 | 2.73 |
| 2009 | 4.42 | 5.96 | 3.12 |
| 2008 | 3.4 | 7.03 | 1.47 |
| 2007 | 7.34 | 14.03 | 2.31 |
| 2006 | 1.61 | 2.38 | 0.88 |
| 2005 | 0.99 | 1.28 | 0.69 |
| 2004 | 1.53 | 2.12 | 1.1 |
| 2003 | 2.11 | 2.55 | 1.63 |
| 2002 | 3.05 | 3.6 | 2.2 |