| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.19 | 1.26 | 1.09 |
| 2024 | 1.29 | 1.43 | 1.08 |
| 2023 | 1.07 | 1.31 | 0.93 |
| 2022 | 1.24 | 1.52 | 1.05 |
| 2021 | 1.05 | 1.77 | 0.82 |
| 2020 | 1.04 | 1.17 | 0.93 |
| 2019 | 1.2 | 1.42 | 0.99 |
| 2018 | 1.2 | 1.69 | 0.87 |
| 2017 | 1.92 | 2.45 | 1.61 |
| 2016 | 1.76 | 2.18 | 1.35 |
| 2015 | 2.3 | 3.91 | 1.71 |
| 2014 | 1.29 | 2.17 | 1 |
| 2013 | 1.44 | 2.01 | 0.99 |
| 2012 | 2.36 | 3.14 | 1.6 |
| 2011 | 2.65 | 3.28 | 2.22 |
| 2010 | 2.27 | 2.87 | 1.82 |
| 2009 | 1.65 | 2.4 | 0.78 |
| 2008 | 1.36 | 2.47 | 0.58 |
| 2007 | 2.18 | 3.25 | 1.04 |
| 2006 | 1.06 | 1.28 | 0.82 |
| 2005 | 1.35 | 1.74 | 1.07 |
| 2004 | 2.29 | 4.3 | 1.44 |