| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.28 | 1.38 | 1.15 |
| 2024 | 1.13 | 1.41 | 0.91 |
| 2023 | 1.03 | 1.21 | 0.88 |
| 2022 | 1.02 | 1.3 | 0.84 |
| 2021 | 1.7 | 2.29 | 1.12 |
| 2020 | 1.91 | 2.44 | 1.43 |
| 2019 | 1.61 | 2.08 | 1.15 |
| 2018 | 1.71 | 2.5 | 1.14 |
| 2017 | 1.84 | 2.17 | 1.42 |
| 2016 | 1.15 | 1.83 | 0.89 |
| 2015 | 0.99 | 1.4 | 0.71 |
| 2014 | 0.74 | 0.87 | 0.64 |
| 2013 | 0.81 | 0.93 | 0.68 |
| 2012 | 0.73 | 0.81 | 0.61 |
| 2011 | 0.85 | 1.14 | 0.57 |
| 2010 | 1.02 | 1.43 | 0.78 |
| 2009 | 0.98 | 1.44 | 0.51 |
| 2008 | 0.79 | 1.45 | 0.41 |
| 2007 | 0.92 | 1.35 | 0.41 |
| 2006 | 0.35 | 0.42 | 0.29 |
| 2005 | 0.34 | 0.41 | 0.25 |
| 2004 | 0.39 | 0.56 | 0.26 |