| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.98 | 2.42 | 1.74 |
| 2024 | 2.29 | 2.88 | 1.75 |
| 2023 | 3.58 | 4.91 | 2.36 |
| 2022 | 4.72 | 5.7 | 3.31 |
| 2021 | 3.62 | 5.82 | 2.3 |
| 2020 | 2.07 | 3.86 | 1.43 |
| 2019 | 1.75 | 2.19 | 1.37 |
| 2018 | 1.84 | 2.68 | 1.34 |
| 2017 | 3.19 | 4.28 | 2.52 |
| 2016 | 3.51 | 3.97 | 2.93 |
| 2015 | 5.2 | 8.51 | 3.02 |
| 2014 | 3.71 | 6.13 | 2.42 |
| 2013 | 3.41 | 4.52 | 1.83 |
| 2012 | 2.2 | 3.15 | 1.44 |
| 2011 | 4.12 | 6.04 | 2.12 |
| 2010 | 4.76 | 7.1 | 3.11 |
| 2009 | 4.69 | 10.9 | 2.69 |
| 2008 | 9.41 | 41.22 | 2.6 |
| 2007 | 19.19 | 38.33 | 6.08 |
| 2006 | 4.53 | 8.04 | 2.7 |
| 2005 | 2.96 | 3.83 | 2.45 |
| 2004 | 4.27 | 5.59 | 3.06 |
| 2003 | 5.85 | 7.43 | 4.33 |
| 2002 | 7.43 | 8.7 | 4.24 |
| 2001 | 8.3 | 10.51 | 6.2 |
| 2000 | 7.21 | 9.84 | 4.27 |
| 1999 | 4.97 | 5.83 | 3.83 |
| 1998 | 5.47 | 8.27 | 4.21 |
| 1997 | 6.18 | 8.47 | 4.64 |