| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.97 | 2.18 | 1.8 |
| 2024 | 1.51 | 2.42 | 1.04 |
| 2023 | 1.28 | 1.49 | 1.09 |
| 2022 | 1.09 | 1.37 | 0.93 |
| 2021 | 1.39 | 1.88 | 1.23 |
| 2020 | 1.42 | 1.74 | 1.07 |
| 2019 | 1.24 | 1.49 | 1.08 |
| 2018 | 1.45 | 1.8 | 1.05 |
| 2017 | 1.83 | 2.29 | 1.47 |
| 2016 | 2.62 | 3.84 | 1.71 |
| 2015 | 4.4 | 5.25 | 3.2 |
| 2014 | 3.13 | 4.19 | 2.26 |
| 2013 | 2.12 | 2.95 | 1.4 |
| 2012 | 1.73 | 2.18 | 1.19 |
| 2011 | 3.05 | 4.25 | 1.88 |
| 2010 | 4.07 | 5.14 | 2.87 |
| 2009 | 3.41 | 4.71 | 2.34 |
| 2008 | 4.38 | 10.34 | 1.6 |
| 2007 | 9.63 | 13.72 | 6.99 |
| 2006 | 5.53 | 7.29 | 3.25 |
| 2005 | 3.73 | 4.79 | 2.58 |
| 2004 | 4.5 | 7.13 | 3.03 |