| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.19 | 1.45 | 1.06 |
| 2024 | 1.11 | 1.68 | 0.82 |
| 2023 | 1.22 | 1.56 | 0.94 |
| 2022 | 1.03 | 1.23 | 0.81 |
| 2021 | 1.02 | 1.49 | 0.8 |
| 2020 | 1.55 | 1.8 | 1.27 |
| 2019 | 2.15 | 3.13 | 1.57 |
| 2018 | 2.69 | 3.47 | 2.08 |
| 2017 | 4.24 | 4.88 | 3.32 |
| 2016 | 4.3 | 5.07 | 3.12 |
| 2015 | 5.32 | 8.69 | 3.58 |
| 2014 | 4.09 | 4.85 | 3.68 |
| 2013 | 4.12 | 5.55 | 3.17 |
| 2012 | 3.23 | 3.94 | 2.52 |
| 2011 | 4.94 | 9.05 | 3.19 |
| 2010 | 4.89 | 8.01 | 2.82 |
| 2009 | 1.68 | 3.08 | 0.77 |
| 2008 | 1.49 | 3.01 | 0.62 |
| 2007 | 2.48 | 3.95 | 1.34 |
| 2006 | 1.48 | 1.95 | 1.16 |
| 2005 | 1.41 | 1.84 | 0.95 |
| 2004 | 2.19 | 4.23 | 1.1 |