| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.35 | 2.67 | 1.94 |
| 2024 | 2.03 | 2.68 | 1.3 |
| 2023 | 1.49 | 1.69 | 1.32 |
| 2022 | 1.49 | 1.92 | 1.2 |
| 2021 | 1.53 | 1.87 | 1.25 |
| 2020 | 1.31 | 1.51 | 1.08 |
| 2019 | 1.37 | 1.93 | 1.17 |
| 2018 | 1.45 | 1.97 | 1.14 |
| 2017 | 2.25 | 3.04 | 1.74 |
| 2016 | 2.06 | 2.76 | 1.65 |
| 2015 | 2.42 | 3.78 | 1.47 |
| 2014 | 1.01 | 2.23 | 0.76 |
| 2013 | 1.08 | 1.52 | 0.84 |
| 2012 | 1.49 | 1.95 | 1.03 |
| 2011 | 3.07 | 4.95 | 1.51 |
| 2010 | 2.92 | 3.63 | 2.28 |
| 2009 | 2.91 | 3.45 | 2.12 |
| 2008 | 3.94 | 7.67 | 1.49 |
| 2007 | 6.21 | 9.2 | 3.11 |
| 2006 | 1.82 | 3.2 | 0.93 |
| 2005 | 1.03 | 1.43 | 0.75 |
| 2004 | 2.23 | 3.6 | 1.3 |
| 2003 | 3.34 | 3.92 | 2.81 |
| 2002 | 3.7 | 4.22 | 2.62 |
| 2001 | 4.55 | 5.62 | 3.5 |
| 2000 | 4.36 | 7.44 | 1.99 |
| 1999 | 2.29 | 2.91 | 1.75 |
| 1998 | 2.15 | 2.63 | 1.71 |