| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.56 | 0.73 | 0.35 |
| 2024 | 0.62 | 0.87 | 0.41 |
| 2023 | 0.97 | 1.27 | 0.84 |
| 2022 | 1 | 1.69 | 0.82 |
| 2021 | 0.87 | 1.03 | 0.81 |
| 2020 | 0.94 | 1.09 | 0.81 |
| 2019 | 1.07 | 1.5 | 0.88 |
| 2018 | 1.12 | 1.42 | 0.85 |
| 2017 | 1.48 | 1.86 | 1.35 |
| 2016 | 1.47 | 1.87 | 1.32 |
| 2015 | 2.16 | 3.84 | 1.49 |
| 2014 | 1.64 | 2.1 | 1.33 |
| 2013 | 1.49 | 1.93 | 1.27 |
| 2012 | 1.47 | 1.88 | 1.27 |
| 2011 | 1.73 | 2.17 | 1.28 |
| 2010 | 2.28 | 2.84 | 1.88 |
| 2009 | 3.15 | 5.85 | 2.29 |
| 2008 | 4.7 | 9.07 | 2.1 |
| 2007 | 5.66 | 7.82 | 3.37 |
| 2006 | 3.3 | 4.36 | 2.63 |
| 2005 | 3.04 | 4.17 | 2.29 |
| 2004 | 4.68 | 5.84 | 3.79 |
| 2003 | 4.75 | 5.48 | 3.8 |
| 2002 | 4.3 | 5.17 | 3.41 |
| 2001 | 5.83 | 7.4 | 4.02 |
| 2000 | 4.31 | 5.38 | 3.52 |