| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2026 | 2.58 | 2.85 | 2.25 |
| 2025 | 2.69 | 3.34 | 2.08 |
| 2024 | 4.01 | 6.46 | 2.64 |
| 2023 | 5.57 | 6.52 | 4.34 |
| 2022 | 5.14 | 6.92 | 4.18 |
| 2021 | 9.64 | 12.59 | 6.24 |
| 2020 | 11.5 | 14.91 | 8.77 |
| 2019 | 16.86 | 33.32 | 11.19 |
| 2018 | 11.79 | 13.99 | 8.85 |
| 2017 | 14.34 | 25.14 | 9.02 |
| 2016 | 21.3 | 31.99 | 15.32 |
| 2015 | 11.68 | 30.71 | 4.06 |
| 2014 | 2.96 | 5.05 | 2.22 |
| 2013 | 2.44 | 3 | 1.95 |
| 2012 | 2.87 | 3.61 | 2 |
| 2011 | 4.2 | 5.41 | 2.71 |
| 2010 | 4.37 | 6.36 | 3.09 |
| 2009 | 3.41 | 4.19 | 2.16 |
| 2008 | 3.4 | 7.28 | 1.18 |
| 2007 | 4.79 | 7.96 | 1.25 |
| 2006 | 1.84 | 2.26 | 1.17 |
| 2005 | 1.1 | 1.7 | 0.68 |
| 2004 | 1.32 | 2.09 | 0.76 |