| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 5.98 | 8.86 | 3.85 |
| 2024 | 4.24 | 5.8 | 2.72 |
| 2023 | 2.81 | 4.12 | 1.87 |
| 2022 | 2.15 | 2.96 | 1.75 |
| 2021 | 2.23 | 4.37 | 1.41 |
| 2020 | 2.76 | 5.61 | 1.59 |
| 2019 | 2.64 | 5.83 | 0.81 |
| 2018 | 1.4 | 2.23 | 0.85 |
| 2017 | 2.82 | 3.93 | 2 |
| 2016 | 3.04 | 3.66 | 2.29 |
| 2015 | 3.98 | 7.68 | 2.39 |
| 2014 | 2.08 | 3.67 | 1.12 |
| 2013 | 1.29 | 1.61 | 1.03 |
| 2012 | 1.79 | 2.53 | 1.31 |
| 2011 | 3.39 | 4.82 | 2 |
| 2010 | 3.76 | 5.2 | 2.46 |
| 2009 | 4.74 | 7.89 | 1.31 |
| 2008 | 3.27 | 6.68 | 0.82 |
| 2007 | 4.31 | 7.51 | 1.49 |
| 2006 | 1.8 | 3.1 | 1.18 |
| 2005 | 1.15 | 1.63 | 0.74 |
| 2004 | 1.1 | 1.85 | 0.41 |