| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.69 | 2.14 | 1.49 |
| 2024 | 1.55 | 2.04 | 1.22 |
| 2023 | 2.07 | 2.94 | 1.72 |
| 2022 | 3.17 | 3.9 | 2.29 |
| 2021 | 2.44 | 3.69 | 2.06 |
| 2020 | 2.53 | 3.36 | 1.91 |
| 2019 | 2.3 | 2.93 | 1.64 |
| 2018 | 1.74 | 2.25 | 1.42 |
| 2017 | 2.69 | 3.41 | 2.14 |
| 2016 | 2.66 | 3.28 | 2.12 |
| 2015 | 3.41 | 6.36 | 2.16 |
| 2014 | 2.43 | 3.28 | 1.81 |
| 2013 | 2.05 | 2.65 | 1.55 |
| 2012 | 1.89 | 2.64 | 1.34 |
| 2011 | 3.61 | 5.36 | 1.79 |
| 2010 | 4.4 | 6.14 | 3.04 |
| 2009 | 2.98 | 3.84 | 2.05 |
| 2008 | 4.19 | 11.74 | 1.11 |
| 2007 | 6.1 | 8.7 | 3.57 |
| 2006 | 2.65 | 5.25 | 0.9 |
| 2005 | 1.03 | 1.54 | 0.77 |
| 2004 | 1.81 | 2.57 | 1.26 |
| 2003 | 2.55 | 3.26 | 1.89 |
| 2002 | 5.52 | 10.76 | 3.37 |