| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.58 | 1.86 | 1.31 |
| 2024 | 1.22 | 2.05 | 0.81 |
| 2023 | 1.54 | 2.18 | 1.24 |
| 2022 | 1.57 | 2.61 | 1.08 |
| 2021 | 0.95 | 1.12 | 0.72 |
| 2020 | 1.41 | 2 | 0.96 |
| 2019 | 1.25 | 1.74 | 0.79 |
| 2018 | 1.1 | 1.54 | 0.76 |
| 2017 | 1.99 | 2.6 | 1.08 |
| 2016 | 3.52 | 5.44 | 2.48 |
| 2015 | 4.62 | 8.84 | 2.23 |
| 2014 | 2.85 | 10.69 | 1.5 |
| 2013 | 1.34 | 1.84 | 0.88 |
| 2012 | 1.07 | 1.46 | 0.78 |
| 2011 | 1.59 | 2.04 | 1.45 |
| 2010 | 1.66 | 2.07 | 1.16 |
| 2009 | 1.24 | 1.77 | 0.7 |
| 2008 | 1.04 | 1.89 | 0.55 |
| 2007 | 1.61 | 2.23 | 0.98 |
| 2006 | 0.92 | 1.2 | 0.67 |
| 2005 | 0.64 | 0.85 | 0.48 |
| 2004 | 1.28 | 2.65 | 0.55 |