| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.25 | 7.03 | 2.61 |
| 2024 | 1.64 | 2.79 | 1.28 |
| 2023 | 2.01 | 2.27 | 1.8 |
| 2022 | 1.96 | 2.99 | 1.64 |
| 2021 | 1.71 | 2.15 | 1.42 |
| 2020 | 1.31 | 1.76 | 0.99 |
| 2019 | 1.47 | 1.89 | 1.17 |
| 2018 | 1.5 | 2.02 | 1.26 |
| 2017 | 3.75 | 7.58 | 1.99 |
| 2016 | 4.24 | 5.93 | 3.08 |
| 2015 | 2.74 | 5.05 | 1.5 |
| 2014 | 1.3 | 1.75 | 0.97 |
| 2013 | 1.13 | 1.3 | 0.92 |
| 2012 | 1.26 | 1.43 | 1.07 |
| 2011 | 1.69 | 2.27 | 1.11 |
| 2010 | 2.41 | 2.84 | 1.92 |
| 2009 | 2.19 | 2.82 | 1.61 |
| 2008 | 2.84 | 4.8 | 1.35 |
| 2007 | 3.02 | 3.85 | 2.23 |
| 2006 | 1.48 | 2.34 | 0.94 |
| 2005 | 0.86 | 1.05 | 0.59 |
| 2004 | 0.92 | 1.29 | 0.7 |