| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 6.75 | 9.43 | 5.75 |
| 2024 | 6.99 | 9.51 | 4.93 |
| 2023 | 7.48 | 10.85 | 5.92 |
| 2022 | 8.74 | 10.25 | 7.05 |
| 2021 | 8.19 | 15.68 | 2.98 |
| 2020 | 3.56 | 4.46 | 2.88 |
| 2019 | 3.54 | 5.04 | 2.52 |
| 2018 | 2.34 | 3.1 | 1.9 |
| 2017 | 2.73 | 4.61 | 1.91 |
| 2016 | 2.08 | 3.91 | 0.81 |
| 2015 | 1.29 | 2.31 | 0.69 |
| 2014 | 0.8 | 1.29 | 0.55 |
| 2013 | 0.7 | 0.85 | 0.55 |
| 2012 | 0.85 | 1.1 | 0.64 |
| 2011 | 1.71 | 2.26 | 0.81 |
| 2010 | 1.67 | 2.35 | 1.04 |
| 2009 | 1.11 | 2.3 | 0.42 |
| 2008 | 1.04 | 2.23 | 0.34 |
| 2007 | 1.71 | 2.68 | 0.88 |
| 2006 | 0.9 | 1.09 | 0.68 |
| 2005 | 0.87 | 1.07 | 0.69 |
| 2004 | 1.44 | 2.06 | 0.98 |