| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2026 | 1.78 | 2.34 | 1.51 |
| 2025 | 1.33 | 1.98 | 0.86 |
| 2024 | 0.94 | 1.32 | 0.64 |
| 2023 | 1.49 | 2.4 | 0.92 |
| 2022 | 1.76 | 2.5 | 1.29 |
| 2021 | 2.21 | 2.95 | 1.78 |
| 2020 | 2.07 | 2.76 | 1.75 |
| 2019 | 2.07 | 2.87 | 1.52 |
| 2018 | 2.74 | 4.58 | 1.65 |
| 2017 | 3.77 | 5.17 | 2.82 |
| 2016 | 4.26 | 5.12 | 3.21 |
| 2015 | 3.19 | 6.39 | 1.72 |
| 2014 | 1.81 | 2.21 | 1.48 |
| 2013 | 2 | 3 | 1.12 |
| 2012 | 1.51 | 1.9 | 0.96 |
| 2011 | 2.65 | 3.19 | 1.4 |
| 2010 | 3.04 | 4.09 | 2.47 |
| 2009 | 1.7 | 3.3 | 0.64 |
| 2008 | 1.19 | 2.28 | 0.48 |
| 2007 | 1.51 | 2.52 | 0.7 |
| 2006 | 0.71 | 1.04 | 0.52 |
| 2005 | 0.68 | 1.06 | 0.5 |
| 2004 | 1.54 | 2.67 | 0.79 |