| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.9 | 2.22 | 1.72 |
| 2024 | 2.12 | 3.02 | 1.61 |
| 2023 | 4.11 | 7.48 | 2.44 |
| 2022 | 5.67 | 7.98 | 3.24 |
| 2021 | 5.69 | 8.86 | 3.89 |
| 2020 | 5.08 | 8.28 | 1.62 |
| 2019 | 1.38 | 2.09 | 0.81 |
| 2018 | 1.2 | 1.82 | 0.75 |
| 2017 | 2.06 | 2.73 | 1.74 |
| 2016 | 2.45 | 3.69 | 1.9 |
| 2015 | 4.26 | 7 | 2.08 |
| 2014 | 2.93 | 3.76 | 1.78 |
| 2013 | 1.68 | 2.28 | 1.32 |
| 2012 | 1.78 | 2.59 | 1.16 |
| 2011 | 3.05 | 4.43 | 1.76 |
| 2010 | 4.48 | 6.5 | 3.67 |
| 2009 | 3.65 | 4.77 | 1.66 |
| 2008 | 3.01 | 6.9 | 1.13 |
| 2007 | 6.2 | 8 | 3.43 |
| 2006 | 2.47 | 3.45 | 1.44 |
| 2005 | 1.65 | 2.2 | 1.13 |
| 2004 | 2.17 | 2.85 | 1.69 |
| 2003 | 2.66 | 3.52 | 1.94 |