| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.69 | 3.89 | 1.83 |
| 2024 | 1.89 | 2.75 | 1.41 |
| 2023 | 2.77 | 3.41 | 2.18 |
| 2022 | 3.34 | 3.96 | 2.58 |
| 2021 | 3.01 | 3.63 | 2.43 |
| 2020 | 3.17 | 3.76 | 2.64 |
| 2019 | 2.91 | 3.53 | 1.93 |
| 2018 | 2.2 | 2.94 | 1.7 |
| 2017 | 3.39 | 4.7 | 2.48 |
| 2016 | 4 | 5.71 | 2.91 |
| 2015 | 6.14 | 11.41 | 3.2 |
| 2014 | 2.8 | 3.51 | 2.12 |
| 2013 | 2.38 | 2.8 | 1.89 |
| 2012 | 2.03 | 2.54 | 1.52 |
| 2011 | 3.52 | 4.99 | 1.95 |
| 2010 | 3.69 | 4.89 | 2.55 |
| 2009 | 2.47 | 4.48 | 1.38 |
| 2008 | 2.82 | 5.9 | 1.06 |
| 2007 | 3.46 | 5.02 | 1.72 |
| 2006 | 1.65 | 2.08 | 1.11 |
| 2005 | 1.44 | 2.02 | 1.04 |
| 2004 | 2.58 | 3.61 | 1.87 |
| 2003 | 3.3 | 4.01 | 2.55 |
| 2002 | 5.13 | 6.23 | 3.51 |
| 2001 | 7.59 | 10.87 | 5.38 |