| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.35 | 1.49 | 1.19 |
| 2024 | 1.55 | 1.97 | 1.23 |
| 2023 | 2.55 | 3.74 | 1.76 |
| 2022 | 7.62 | 16.04 | 3.07 |
| 2021 | 11.96 | 13.67 | 10.51 |
| 2020 | 11.13 | 19.39 | 7.5 |
| 2019 | 8.22 | 11.83 | 6.01 |
| 2018 | 4.47 | 8.5 | 1.68 |
| 2017 | 3.5 | 4.28 | 2.86 |
| 2016 | 2.52 | 3.9 | 1.72 |
| 2015 | 2.92 | 3.76 | 1.62 |
| 2014 | 1.35 | 1.85 | 0.9 |
| 2013 | 1.02 | 1.3 | 0.81 |
| 2012 | 1.55 | 2.3 | 1.02 |
| 2011 | 2.31 | 3.1 | 1.69 |
| 2010 | 1.99 | 2.71 | 1.37 |
| 2009 | 2.06 | 2.88 | 1.36 |
| 2008 | 3.1 | 5.39 | 1.14 |
| 2007 | 2.62 | 4.22 | 1.13 |
| 2006 | 1.15 | 1.58 | 0.79 |
| 2005 | 0.88 | 1.07 | 0.66 |
| 2004 | 1.29 | 1.66 | 0.88 |
| 2003 | 1.43 | 1.77 | 1.11 |
| 2002 | 1.65 | 1.97 | 1.21 |
| 2001 | 2.62 | 4 | 1.64 |
| 2000 | 2.57 | 3.09 | 1.53 |
| 1999 | 1.88 | 2.58 | 1.55 |
| 1998 | 3.59 | 5.18 | 2.42 |