| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.83 | 5 | 3.29 |
| 2024 | 3.53 | 4.72 | 2.66 |
| 2023 | 3.3 | 4.63 | 2.56 |
| 2022 | 2.66 | 3.56 | 2 |
| 2021 | 2.42 | 2.89 | 2.11 |
| 2020 | 2.76 | 3.79 | 2.15 |
| 2019 | 2.7 | 3.36 | 2.33 |
| 2018 | 2.74 | 4.53 | 1.85 |
| 2017 | 4.08 | 5.5 | 3.02 |
| 2016 | 4.92 | 5.64 | 3.85 |
| 2015 | 5.38 | 9.91 | 3.31 |
| 2014 | 3.33 | 4.67 | 2.52 |
| 2013 | 2.61 | 3.02 | 2.21 |
| 2012 | 2.74 | 3.44 | 2.03 |
| 2011 | 3.65 | 4.56 | 2.72 |
| 2010 | 3.63 | 5.16 | 2.78 |
| 2009 | 2.6 | 3.29 | 1.82 |
| 2008 | 2.43 | 4.14 | 1.32 |
| 2007 | 3.27 | 4.68 | 2 |
| 2006 | 1.61 | 2.09 | 1.36 |
| 2005 | 1.4 | 1.66 | 1.17 |
| 2004 | 2.12 | 3.13 | 1.33 |
| 2003 | 2.78 | 3.56 | 2.12 |