| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2026 | 4.75 | 5.01 | 4.31 |
| 2025 | 4.64 | 5.64 | 4.14 |
| 2024 | 3.86 | 4.63 | 3.01 |
| 2023 | 4.5 | 5.74 | 3.63 |
| 2022 | 4.2 | 4.97 | 3.64 |
| 2021 | 3.76 | 5.23 | 2.91 |
| 2020 | 3.24 | 5.42 | 2.5 |
| 2019 | 3.31 | 4.3 | 2.76 |
| 2018 | 3.08 | 4.06 | 2.31 |
| 2017 | 4.69 | 6.46 | 3.53 |
| 2016 | 5.09 | 6.61 | 3.82 |
| 2015 | 3.92 | 6.33 | 2.2 |
| 2014 | 2.34 | 3.04 | 1.86 |
| 2013 | 2.08 | 2.33 | 1.86 |
| 2012 | 2.07 | 2.65 | 1.68 |
| 2011 | 2.88 | 3.67 | 1.85 |
| 2010 | 2.94 | 3.58 | 2.39 |
| 2009 | 1.86 | 2.63 | 1.33 |
| 2008 | 1.77 | 2.96 | 1.02 |
| 2007 | 2.23 | 3.07 | 1.44 |
| 2006 | 1.7 | 2.37 | 1.31 |
| 2005 | 1.68 | 2.19 | 1.02 |
| 2004 | 1.51 | 2.3 | 1.08 |