| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.57 | 1.7 | 1.5 |
| 2024 | 1.63 | 2.04 | 1.38 |
| 2023 | 1.67 | 2.26 | 1.47 |
| 2022 | 1.66 | 2.02 | 1.47 |
| 2021 | 2.4 | 3.35 | 1.74 |
| 2020 | 3.56 | 5.06 | 2.45 |
| 2019 | 3.18 | 3.84 | 2.77 |
| 2018 | 3.21 | 3.75 | 2.72 |
| 2017 | 3.73 | 4.96 | 3.2 |
| 2016 | 4.14 | 5.35 | 3.53 |
| 2015 | 5.26 | 8.65 | 3.12 |
| 2014 | 2.57 | 3.56 | 2.28 |
| 2013 | 2.83 | 3.16 | 2.57 |
| 2012 | 2.78 | 3.35 | 2.17 |
| 2011 | 3.9 | 4.97 | 2.74 |
| 2010 | 4.72 | 5.76 | 4.08 |
| 2009 | 4.82 | 5.67 | 4.2 |
| 2008 | 6.79 | 12.26 | 4.3 |
| 2007 | 10.27 | 13.66 | 6.33 |
| 2006 | 5.01 | 6.13 | 3.94 |
| 2005 | 6.07 | 7.43 | 4.48 |
| 2004 | 6.87 | 11.4 | 4.24 |