| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.31 | 5.83 | 3.67 |
| 2024 | 3.42 | 4.25 | 2.34 |
| 2023 | 2.79 | 3.51 | 2.26 |
| 2022 | 2.86 | 3.6 | 2.02 |
| 2021 | 2.41 | 4.27 | 1.65 |
| 2020 | 1.53 | 2.03 | 1.32 |
| 2019 | 1.62 | 2.26 | 1.39 |
| 2018 | 1.93 | 2.52 | 1.47 |
| 2017 | 2.33 | 2.85 | 1.91 |
| 2016 | 2.78 | 5.7 | 2.05 |
| 2015 | 2.99 | 5.88 | 1.6 |
| 2014 | 1.47 | 1.81 | 1.13 |
| 2013 | 1.82 | 2.46 | 1.4 |
| 2012 | 2.71 | 4.12 | 1.88 |
| 2011 | 6.78 | 11.34 | 2.88 |
| 2010 | 3.64 | 6.52 | 2.41 |
| 2009 | 2.27 | 3.27 | 1.15 |
| 2008 | 2.49 | 5.29 | 0.92 |
| 2007 | 3.28 | 4.45 | 1.69 |
| 2006 | 1.7 | 2.06 | 1.39 |
| 2005 | 1.39 | 1.88 | 0.88 |
| 2004 | 1.9 | 2.26 | 1.23 |
| 2003 | 2.07 | 2.36 | 1.64 |
| 2002 | 2.52 | 2.84 | 2.03 |
| 2001 | 4.74 | 5.49 | 3.88 |
| 2000 | 4.58 | 6.11 | 4.04 |
| 1999 | 3.7 | 4.84 | 2.66 |