| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.31 | 1.55 | 1.17 |
| 2024 | 1.25 | 2.17 | 0.76 |
| 2023 | 1.38 | 1.6 | 1.17 |
| 2022 | 1.47 | 1.85 | 1.06 |
| 2021 | 1.36 | 1.93 | 1.04 |
| 2020 | 1.23 | 1.6 | 1 |
| 2019 | 1.53 | 2.9 | 0.9 |
| 2018 | 0.99 | 1.27 | 0.81 |
| 2017 | 1.64 | 2.52 | 1.18 |
| 2016 | 1.73 | 2.06 | 1.38 |
| 2015 | 2.37 | 3.75 | 1.47 |
| 2014 | 1.95 | 2.71 | 1.46 |
| 2013 | 1.59 | 2.23 | 1.15 |
| 2012 | 1.99 | 2.75 | 1.29 |
| 2011 | 4.04 | 7.35 | 2.08 |
| 2010 | 5.22 | 7.97 | 3.22 |
| 2009 | 3.31 | 4.72 | 1.8 |
| 2008 | 3.97 | 8.55 | 1.33 |
| 2007 | 3.91 | 6.34 | 1.4 |
| 2006 | 1.45 | 1.91 | 1.13 |
| 2005 | 1.26 | 1.91 | 0.9 |
| 2004 | 1.79 | 2.46 | 1.43 |
| 2003 | 2.27 | 3.02 | 1.6 |
| 2002 | 3.19 | 3.76 | 2.48 |
| 2001 | 6.07 | 7.14 | 4.4 |