| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.51 | 1.79 | 1.35 |
| 2024 | 1.19 | 1.71 | 0.94 |
| 2023 | 1.23 | 1.36 | 1.1 |
| 2022 | 1.26 | 1.52 | 1.07 |
| 2021 | 1.5 | 1.73 | 1.33 |
| 2020 | 1.61 | 2.22 | 1.3 |
| 2019 | 1.43 | 1.85 | 1.2 |
| 2018 | 1.76 | 2.55 | 1.09 |
| 2017 | 2.6 | 3.09 | 2.18 |
| 2016 | 3.38 | 4.72 | 2.81 |
| 2015 | 4.13 | 7.1 | 2.24 |
| 2014 | 2.15 | 3.1 | 0.89 |
| 2013 | 1.05 | 1.34 | 0.86 |
| 2012 | 1.05 | 1.36 | 0.81 |
| 2011 | 1.77 | 2.41 | 1.09 |
| 2010 | 2.2 | 3.14 | 1.42 |
| 2009 | 1.51 | 1.89 | 0.68 |
| 2008 | 1.67 | 3.65 | 0.61 |
| 2007 | 2.87 | 4.38 | 1.4 |
| 2006 | 1.21 | 1.5 | 0.95 |
| 2005 | 1.17 | 1.54 | 0.79 |
| 2004 | 1.19 | 1.9 | 0.52 |