| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.31 | 1.54 | 1.22 |
| 2024 | 1.39 | 1.61 | 1.1 |
| 2023 | 2.09 | 2.7 | 1.52 |
| 2022 | 2.6 | 3.89 | 1.99 |
| 2021 | 2.91 | 3.58 | 2.27 |
| 2020 | 2.09 | 3.01 | 1.49 |
| 2019 | 2.14 | 2.87 | 1.71 |
| 2018 | 2.91 | 3.93 | 1.93 |
| 2017 | 5.86 | 16.22 | 2.41 |
| 2016 | 4.57 | 8.9 | 3.68 |
| 2015 | 3.67 | 6.1 | 3.25 |
| 2014 | 3.23 | 3.61 | 2.83 |
| 2013 | 3.1 | 3.63 | 2.59 |
| 2012 | 2.85 | 3.45 | 2.24 |
| 2011 | 4.25 | 6.28 | 2.82 |
| 2010 | 4.93 | 6.49 | 3.66 |
| 2009 | 3.59 | 4.94 | 2.13 |
| 2008 | 5.44 | 12.91 | 1.46 |
| 2007 | 9.09 | 14.92 | 4.64 |
| 2006 | 3.07 | 5.34 | 1.87 |
| 2005 | 1.8 | 2.12 | 1.41 |
| 2004 | 2.79 | 4.18 | 1.91 |
| 2003 | 4.19 | 4.96 | 2.8 |
| 2002 | 5.21 | 6.27 | 4.33 |
| 2001 | 7.25 | 9.38 | 4.69 |