| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.45 | 3.56 | 1.94 |
| 2024 | 1.58 | 2.81 | 0.98 |
| 2023 | 2.85 | 5.91 | 1.24 |
| 2022 | 4.02 | 5.39 | 2.8 |
| 2021 | 4.52 | 9.2 | 2.15 |
| 2020 | 1.29 | 2.06 | 0.84 |
| 2019 | 1.29 | 2.09 | 1.04 |
| 2018 | 1.78 | 2.92 | 1.17 |
| 2017 | 3.26 | 6.87 | 1.73 |
| 2016 | 3.63 | 6.95 | 2.31 |
| 2015 | 4.26 | 8.72 | 2.77 |
| 2014 | 2.78 | 3.43 | 2.15 |
| 2013 | 1.89 | 2.79 | 1.29 |
| 2012 | 1.35 | 1.72 | 0.94 |
| 2011 | 2.05 | 2.87 | 0.97 |
| 2010 | 3.29 | 5.14 | 2.19 |
| 2009 | 3.08 | 5.46 | 0.78 |
| 2008 | 1.59 | 3.5 | 0.62 |
| 2007 | 2.51 | 4.09 | 1.05 |
| 2006 | 0.8 | 1.06 | 0.51 |
| 2005 | 0.38 | 0.57 | 0.16 |
| 2004 | 0.43 | 0.79 | 0.26 |