| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.37 | 1.67 | 1.23 |
| 2024 | 1.15 | 1.93 | 0.86 |
| 2023 | 1.43 | 1.91 | 1.18 |
| 2022 | 1.43 | 1.8 | 1.2 |
| 2021 | 1.64 | 2.02 | 1.41 |
| 2020 | 2.38 | 2.75 | 1.58 |
| 2019 | 3.64 | 6.2 | 2.41 |
| 2018 | 4.17 | 5.01 | 3.54 |
| 2017 | 6.24 | 11.1 | 3.81 |
| 2016 | 7.22 | 22.21 | 4.05 |
| 2015 | 4.61 | 5.1 | 3.11 |
| 2014 | 4.44 | 9.39 | 2.73 |
| 2013 | 8.87 | 10.22 | 7.42 |
| 2012 | 8.43 | 10.28 | 6.68 |
| 2011 | 11.57 | 15.25 | 7.01 |
| 2010 | 9.08 | 15.32 | 5.19 |
| 2009 | 4.14 | 5.28 | 2.26 |
| 2008 | 3.89 | 7.69 | 1.69 |
| 2007 | 5.73 | 9.15 | 2.84 |
| 2006 | 2.82 | 3.35 | 2.29 |
| 2005 | 2.68 | 3.84 | 1.88 |
| 2004 | 3.41 | 5.5 | 2.24 |
| 2003 | 3.1 | 3.74 | 2.31 |
| 2002 | 3.67 | 4.6 | 2.01 |
| 2001 | 6.24 | 7.05 | 4.8 |
| 2000 | 7.4 | 11.59 | 6.54 |
| 1999 | 6.11 | 8.29 | 2.81 |