| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.78 | 3.01 | 2.61 |
| 2024 | 2.77 | 3.41 | 2.32 |
| 2023 | 2.81 | 3.22 | 2.4 |
| 2022 | 1.89 | 2.76 | 1.36 |
| 2021 | 1.43 | 1.61 | 1.18 |
| 2020 | 1.24 | 1.54 | 0.97 |
| 2019 | 1.38 | 1.82 | 1.22 |
| 2018 | 1.72 | 2.55 | 1.16 |
| 2017 | 1.86 | 2.45 | 1.56 |
| 2016 | 1.69 | 2.04 | 1.45 |
| 2015 | 2.34 | 4.19 | 1.26 |
| 2014 | 0.83 | 1.66 | 0.66 |
| 2013 | 0.95 | 1.26 | 0.76 |
| 2012 | 1.3 | 1.64 | 0.99 |
| 2011 | 3.14 | 6.42 | 1.36 |
| 2010 | 5.37 | 8.09 | 4.08 |
| 2009 | 4.45 | 6.53 | 1.76 |
| 2008 | 3.76 | 10.29 | 1.46 |
| 2007 | 5.67 | 12.19 | 1.79 |
| 2006 | 1.23 | 1.72 | 0.87 |
| 2005 | 0.94 | 1.38 | 0.67 |
| 2004 | 1.3 | 3.13 | 1.07 |