| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.68 | 2.8 | 2.47 |
| 2024 | 2.05 | 3.38 | 1.45 |
| 2023 | 1.69 | 2.43 | 1.19 |
| 2022 | 1.34 | 1.97 | 1.02 |
| 2021 | 1.54 | 2.05 | 1.11 |
| 2020 | 2.14 | 4.12 | 1.22 |
| 2019 | 2.78 | 4.96 | 1.98 |
| 2018 | 2.96 | 4.56 | 2.02 |
| 2017 | 5.35 | 12.5 | 2.33 |
| 2016 | 8.16 | 12.32 | 5 |
| 2015 | 6.93 | 10.3 | 3.9 |
| 2014 | 4.27 | 6.68 | 1.72 |
| 2013 | 2.35 | 4.11 | 1.65 |
| 2012 | 4.84 | 8.84 | 2.25 |
| 2011 | 4.02 | 5.87 | 2.5 |
| 2010 | 5.85 | 8.76 | 4.32 |
| 2009 | 7.79 | 16.37 | 4.66 |
| 2008 | 11.12 | 22.86 | 4.8 |
| 2007 | 17.63 | 32.19 | 4.5 |
| 2006 | 3.25 | 4.95 | 2.08 |
| 2005 | 1.68 | 2.28 | 1.14 |
| 2004 | 1.69 | 2.67 | 1.15 |