| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.04 | 3.55 | 2.74 |
| 2024 | 3.38 | 4.9 | 2.55 |
| 2023 | 5.4 | 7.8 | 3.9 |
| 2022 | 5.73 | 8.04 | 3.13 |
| 2021 | 4.08 | 6.42 | 3.03 |
| 2020 | 2.87 | 4.68 | 0.94 |
| 2019 | 0.91 | 1.2 | 0.64 |
| 2018 | 0.86 | 1.24 | 0.6 |
| 2017 | 1.29 | 1.64 | 1.05 |
| 2016 | 1.03 | 1.5 | 0.72 |
| 2015 | 1.59 | 2.52 | 0.92 |
| 2014 | 0.94 | 1.13 | 0.67 |
| 2013 | 0.64 | 0.88 | 0.51 |
| 2012 | 0.65 | 0.86 | 0.45 |
| 2011 | 1.11 | 1.72 | 0.58 |
| 2010 | 1.22 | 1.67 | 0.96 |
| 2009 | 1.16 | 1.59 | 0.64 |
| 2008 | 1.3 | 3.1 | 0.43 |
| 2007 | 2.76 | 3.82 | 1.21 |
| 2006 | 0.92 | 1.22 | 0.57 |
| 2005 | 0.77 | 1.11 | 0.53 |
| 2004 | 1.24 | 2.29 | 0.74 |