| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2026 | 2.17 | 2.23 | 2.12 |
| 2025 | 2.34 | 2.63 | 2.06 |
| 2024 | 1.86 | 2.43 | 1.14 |
| 2023 | 2.63 | 3.47 | 2.1 |
| 2022 | 3.07 | 4.74 | 2.59 |
| 2021 | 2.85 | 3.37 | 2.47 |
| 2020 | 3.13 | 5.29 | 2.6 |
| 2019 | 3.66 | 5.32 | 2.88 |
| 2018 | 4.14 | 5.27 | 3.04 |
| 2017 | 4.85 | 5.64 | 4.1 |
| 2016 | 5.81 | 7.37 | 5.2 |
| 2015 | 6.65 | 10.52 | 3.85 |
| 2014 | 3.46 | 5.7 | 2.89 |
| 2013 | 3.47 | 4.13 | 2.96 |
| 2012 | 4.37 | 5.47 | 3.04 |
| 2011 | 6.92 | 10.11 | 4.39 |
| 2010 | 5.4 | 7.96 | 3.75 |
| 2009 | 6.29 | 8.21 | 4.67 |
| 2008 | 6.94 | 12.64 | 3.58 |
| 2007 | 7.93 | 10.79 | 4.67 |
| 2006 | 5.78 | 6.92 | 4.69 |
| 2005 | 4.82 | 6.26 | 2.95 |
| 2004 | 5.54 | 10.33 | 3.48 |