| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.35 | 1.44 | 1.28 |
| 2024 | 1.74 | 2.13 | 1.39 |
| 2023 | 1.45 | 1.61 | 1.29 |
| 2022 | 1.35 | 1.84 | 0.88 |
| 2021 | 0.88 | 1.2 | 0.74 |
| 2020 | 0.75 | 0.83 | 0.66 |
| 2019 | 0.92 | 1.09 | 0.77 |
| 2018 | 1.03 | 1.22 | 0.87 |
| 2017 | 1.27 | 1.46 | 1.15 |
| 2016 | 1.15 | 1.45 | 1.08 |
| 2015 | 1.96 | 2.94 | 1.42 |
| 2014 | 1.11 | 2.18 | 0.92 |
| 2013 | 1.3 | 1.85 | 1.05 |
| 2012 | 1.45 | 1.65 | 1.25 |
| 2011 | 1.87 | 2.56 | 1.43 |
| 2010 | 2.42 | 2.93 | 2.04 |
| 2009 | 2.54 | 3.27 | 2.21 |
| 2008 | 2.82 | 5.14 | 1.57 |
| 2007 | 3.72 | 5.39 | 1.71 |
| 2006 | 1.92 | 2.67 | 1.43 |
| 2005 | 2.01 | 2.42 | 1.65 |
| 2004 | 3.15 | 5.72 | 2.09 |
| 2003 | 4.09 | 5.44 | 2.9 |
| 2002 | 4.53 | 6.61 | 3.08 |
| 2001 | 4.99 | 5.59 | 4.02 |
| 2000 | 16.01 | 22.67 | 9.36 |
| 1999 | 13.03 | 17.76 | 11.74 |
| 1998 | 16.18 | 19.9 | 13.21 |