| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.85 | 2.21 | 1.67 |
| 2024 | 1.04 | 2.7 | 0.64 |
| 2023 | 0.91 | 1.17 | 0.83 |
| 2022 | 0.97 | 1.33 | 0.78 |
| 2021 | 1.23 | 1.63 | 0.9 |
| 2020 | 0.84 | 1.3 | 0.72 |
| 2019 | 0.93 | 1.28 | 0.77 |
| 2018 | 1.02 | 1.47 | 0.73 |
| 2017 | 1.75 | 2.07 | 1.41 |
| 2016 | 2.15 | 3.01 | 1.95 |
| 2015 | 3.41 | 5.29 | 2.31 |
| 2014 | 3.67 | 4.81 | 2.79 |
| 2013 | 3.63 | 5.3 | 2.29 |
| 2012 | 2.3 | 2.82 | 1.71 |
| 2011 | 5.72 | 8.19 | 2.41 |
| 2010 | 4.56 | 7.77 | 3.08 |
| 2009 | 3.29 | 4.67 | 1.3 |
| 2008 | 2.27 | 4.44 | 1.02 |
| 2007 | 3.69 | 5.69 | 1.48 |
| 2006 | 1.43 | 1.62 | 1.25 |
| 2005 | 1.64 | 2.42 | 1.17 |
| 2004 | 2.5 | 3.03 | 1.15 |
| 2003 | 2.76 | 3.31 | 2.16 |
| 2002 | 3.72 | 4.37 | 3.18 |
| 2001 | 4.69 | 6.05 | 3.13 |