| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3 | 3.37 | 2.62 |
| 2024 | 2.28 | 3.12 | 1.78 |
| 2023 | 3.39 | 4.1 | 2.51 |
| 2022 | 3.22 | 3.98 | 2.6 |
| 2021 | 3.72 | 6.09 | 2.5 |
| 2020 | 2.77 | 3.46 | 2.21 |
| 2019 | 2.9 | 3.75 | 2.4 |
| 2018 | 2.59 | 3.66 | 2.03 |
| 2017 | 3.23 | 4.46 | 2.52 |
| 2016 | 3.01 | 4.04 | 2.01 |
| 2015 | 2.85 | 4.34 | 1.91 |
| 2014 | 2.01 | 2.65 | 1.52 |
| 2013 | 2.12 | 2.76 | 1.7 |
| 2012 | 3.21 | 6.19 | 1.87 |
| 2011 | 6.32 | 8.12 | 4.06 |
| 2010 | 5.06 | 9.13 | 3.23 |
| 2009 | 3.2 | 4.42 | 1.71 |
| 2008 | 3.62 | 9.25 | 1.25 |
| 2007 | 5.53 | 9.38 | 2.11 |
| 2006 | 2.09 | 2.91 | 1.52 |
| 2005 | 1.59 | 2.36 | 1.03 |
| 2004 | 2.52 | 3.15 | 2.03 |
| 2003 | 2.68 | 3.09 | 2.06 |
| 2002 | 4.79 | 5.93 | 3.96 |
| 2001 | 9.69 | 16.04 | 6.05 |