| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.11 | 1.47 | 0.94 |
| 2024 | 0.93 | 1.15 | 0.75 |
| 2023 | 1.05 | 1.21 | 0.86 |
| 2022 | 0.84 | 1 | 0.71 |
| 2021 | 1.21 | 1.78 | 0.83 |
| 2020 | 1.42 | 2.34 | 1.02 |
| 2019 | 1.05 | 1.73 | 0.89 |
| 2018 | 1.18 | 1.54 | 0.88 |
| 2017 | 1.81 | 2.46 | 1.41 |
| 2016 | 1.79 | 2.29 | 1.29 |
| 2015 | 1.74 | 3.09 | 1.01 |
| 2014 | 1.04 | 1.33 | 0.84 |
| 2013 | 0.96 | 1.17 | 0.82 |
| 2012 | 1.46 | 2.15 | 0.76 |
| 2011 | 2.88 | 3.74 | 2.15 |
| 2010 | 2.6 | 3.22 | 2.04 |
| 2009 | 1.94 | 2.73 | 1.24 |
| 2008 | 2.97 | 6.59 | 0.94 |
| 2007 | 7.36 | 12 | 3.64 |
| 2006 | 3.72 | 4.81 | 2.82 |
| 2005 | 2.7 | 3.52 | 1.98 |
| 2004 | 4.02 | 9.24 | 2.36 |