| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.35 | 1.58 | 1.26 |
| 2024 | 1.57 | 2.17 | 1.15 |
| 2023 | 2.35 | 3.1 | 1.86 |
| 2022 | 3.9 | 6.09 | 2.73 |
| 2021 | 3.99 | 6.97 | 2.7 |
| 2020 | 3.55 | 4.92 | 2.87 |
| 2019 | 5.08 | 11.63 | 1.99 |
| 2018 | 2.63 | 3.75 | 1.76 |
| 2017 | 4.42 | 5.41 | 3.76 |
| 2016 | 20.63 | 66.08 | 3.99 |
| 2015 | 9.26 | 63.33 | 4.61 |
| 2014 | 3.86 | 5.05 | 3.04 |
| 2013 | 3.83 | 5.27 | 2.7 |
| 2012 | 4.02 | 6.12 | 2.41 |
| 2011 | 5.16 | 6.26 | 4.46 |
| 2010 | 5.53 | 6.76 | 4.71 |
| 2009 | 4.62 | 6.13 | 2.9 |
| 2008 | 7.84 | 16.09 | 1.63 |
| 2007 | 7.83 | 16.09 | 3.53 |
| 2006 | 2.79 | 3.83 | 1.72 |
| 2005 | 2.57 | 4.36 | 1.58 |
| 2004 | 5.18 | 6.28 | 4.43 |
| 2003 | 5.13 | 6.54 | 4.23 |
| 2002 | 5.5 | 7.15 | 2.23 |
| 2001 | 4.61 | 6.35 | 3.21 |
| 2000 | 3.48 | 4.34 | 2.47 |
| 1999 | 2.99 | 4.1 | 1.9 |
| 1998 | 3.09 | 3.85 | 2.15 |