| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.25 | 2.72 | 1.87 |
| 2024 | 1.86 | 2.13 | 1.55 |
| 2023 | 2.12 | 2.69 | 1.84 |
| 2022 | 2.79 | 3.55 | 2.42 |
| 2021 | 3.89 | 5.75 | 2.26 |
| 2020 | 5.75 | 7.37 | 4.07 |
| 2019 | 6.11 | 9.16 | 3.14 |
| 2018 | 8.1 | 17.94 | 2.68 |
| 2017 | 7.18 | 17.87 | 4.22 |
| 2016 | 3.85 | 4.65 | 2.78 |
| 2015 | 2.78 | 5.64 | 1.24 |
| 2014 | 1.07 | 1.58 | 0.78 |
| 2013 | 0.73 | 0.9 | 0.59 |
| 2012 | 0.76 | 1.06 | 0.49 |
| 2011 | 1.21 | 1.74 | 0.83 |
| 2010 | 0.99 | 1.21 | 0.77 |
| 2009 | 0.64 | 1.16 | 0.31 |
| 2008 | 0.59 | 1.21 | 0.22 |
| 2007 | 0.83 | 1.08 | 0.59 |
| 2006 | 0.58 | 0.7 | 0.45 |
| 2005 | 0.66 | 0.93 | 0.47 |
| 2004 | 0.73 | 0.8 | 0.67 |