| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 5.72 | 7.1 | 4.41 |
| 2024 | 3.95 | 5.06 | 2.96 |
| 2023 | 2.87 | 5.11 | 2.07 |
| 2022 | 2.08 | 3.29 | 1.65 |
| 2021 | 2.05 | 2.83 | 1.42 |
| 2020 | 1.91 | 3.42 | 1.21 |
| 2019 | 2.85 | 5.71 | 1.35 |
| 2018 | 4.33 | 5.73 | 3.04 |
| 2017 | 5.46 | 10.24 | 3.14 |
| 2016 | 10.2 | 16.8 | 8.24 |
| 2015 | 6.13 | 12.67 | 2.81 |
| 2014 | 2.6 | 3.51 | 2.02 |
| 2013 | 3.3 | 4.45 | 2.4 |
| 2012 | 3.34 | 4.28 | 2.56 |
| 2011 | 5.05 | 6.3 | 3.43 |
| 2010 | 5.84 | 8.2 | 4.49 |
| 2009 | 6.9 | 8.92 | 4.22 |
| 2008 | 5.94 | 10.03 | 3.01 |
| 2007 | 10.72 | 17.87 | 4.76 |
| 2006 | 3.29 | 5.1 | 1.98 |
| 2005 | 1.88 | 2.55 | 1.46 |
| 2004 | 2.45 | 4.37 | 1.51 |