| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.67 | 2.42 | 1.3 |
| 2024 | 1.88 | 2.49 | 1.35 |
| 2023 | 2.38 | 2.85 | 1.97 |
| 2022 | 2.58 | 3.23 | 1.86 |
| 2021 | 2.13 | 4.8 | 1.02 |
| 2020 | 1.11 | 1.49 | 0.85 |
| 2019 | 1.22 | 1.54 | 1.06 |
| 2018 | 1.1 | 1.3 | 0.93 |
| 2017 | 1.25 | 1.66 | 0.96 |
| 2016 | 1.21 | 1.77 | 0.92 |
| 2015 | 1.52 | 2.33 | 0.82 |
| 2014 | 0.99 | 1.72 | 0.77 |
| 2013 | 1 | 1.21 | 0.85 |
| 2012 | 1.36 | 2.07 | 0.84 |
| 2011 | 2.62 | 3.62 | 1.5 |
| 2010 | 3.97 | 5.92 | 2.24 |
| 2009 | 3.39 | 6.16 | 1.47 |
| 2008 | 4.66 | 11.3 | 1.09 |
| 2007 | 5.13 | 8.45 | 1.74 |
| 2006 | 1.71 | 2.4 | 1.2 |
| 2005 | 1.03 | 1.4 | 0.6 |
| 2004 | 1.3 | 2.5 | 0.75 |