| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.76 | 3.74 | 2.35 |
| 2024 | 2.32 | 3.89 | 1.18 |
| 2023 | 2.36 | 2.85 | 1.66 |
| 2022 | 2.59 | 3.63 | 1.98 |
| 2021 | 2.87 | 3.91 | 2.24 |
| 2020 | 2.88 | 3.49 | 2.38 |
| 2019 | 3.25 | 4.2 | 2.53 |
| 2018 | 3.52 | 4.7 | 2.48 |
| 2017 | 7.43 | 10.53 | 4.58 |
| 2016 | 9.91 | 12.05 | 8.37 |
| 2015 | 10.56 | 20.71 | 7.41 |
| 2014 | 5.63 | 10.7 | 3.61 |
| 2013 | 5.93 | 8.62 | 3.61 |
| 2012 | 4.15 | 5.24 | 3.45 |
| 2011 | 7.94 | 11.54 | 4.07 |
| 2010 | 12.48 | 16.49 | 7.88 |
| 2009 | 5.64 | 9.37 | 1.81 |
| 2008 | 2.3 | 4.24 | 1.18 |
| 2007 | 3.3 | 4.62 | 2.1 |
| 2006 | 2.25 | 3.31 | 1.74 |
| 2005 | 1.65 | 2.02 | 1.18 |