| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2024 | 2.24 | 2.79 | 1.56 |
| 2023 | 1.54 | 1.85 | 1.17 |
| 2022 | 1.17 | 1.46 | 0.89 |
| 2021 | 1.05 | 1.51 | 0.84 |
| 2020 | 1.14 | 1.51 | 0.82 |
| 2019 | 1.19 | 1.52 | 0.92 |
| 2018 | 1.15 | 1.57 | 0.76 |
| 2017 | 2.28 | 3.58 | 1.49 |
| 2016 | 3.01 | 3.59 | 2.48 |
| 2015 | 4.09 | 5.32 | 3.03 |
| 2014 | 3.08 | 4.92 | 2.38 |
| 2013 | 2.68 | 3.32 | 2.12 |
| 2012 | 2.33 | 3.1 | 1.77 |
| 2011 | 3.14 | 4.31 | 2.28 |
| 2010 | 4.81 | 8.09 | 2.59 |
| 2009 | 6.28 | 8.06 | 4.41 |
| 2008 | 4.51 | 7.58 | 2.95 |
| 2007 | 6.96 | 9.06 | 5.09 |
| 2006 | 3.9 | 5.56 | 2.12 |
| 2005 | 1.49 | 2.06 | 1.11 |
| 2004 | 2.35 | 2.9 | 1.41 |
| 2003 | 2.85 | 3.6 | 1.97 |
| 2002 | 3.23 | 3.48 | 2.96 |