| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.14 | 1.25 | 1.04 |
| 2024 | 1.17 | 1.71 | 0.89 |
| 2023 | 1.76 | 2.07 | 1.52 |
| 2022 | 1.63 | 2.85 | 1.12 |
| 2021 | 1.39 | 1.89 | 1.18 |
| 2020 | 1.94 | 2.8 | 1.51 |
| 2019 | 3.58 | 4.89 | 2.6 |
| 2018 | 5 | 7.92 | 3.28 |
| 2017 | 7.55 | 9.41 | 6.02 |
| 2016 | 8.75 | 11.63 | 5.61 |
| 2015 | 6.79 | 11.92 | 4.67 |
| 2014 | 4.35 | 5.87 | 2.93 |
| 2013 | 3.03 | 3.5 | 2.62 |
| 2012 | 2.79 | 3.77 | 2.13 |
| 2011 | 5.55 | 7.28 | 2.67 |
| 2010 | 6.19 | 8.44 | 4.24 |
| 2009 | 5.13 | 8.79 | 3 |
| 2008 | 3.97 | 6.84 | 2.27 |
| 2007 | 5.78 | 8.7 | 3.43 |
| 2006 | 3.79 | 5.12 | 2.86 |
| 2005 | 3.09 | 3.96 | 2.43 |
| 2004 | 4.78 | 9.6 | 2.53 |