| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.27 | 1.71 | 0.98 |
| 2024 | 0.9 | 1.61 | 0.7 |
| 2023 | 1.26 | 1.55 | 1.04 |
| 2022 | 1.45 | 1.86 | 1.18 |
| 2021 | 2.51 | 3.45 | 1.66 |
| 2020 | 14.92 | 46.68 | 3.08 |
| 2019 | 4.13 | 50.03 | 1.37 |
| 2018 | 2 | 3.38 | 1.32 |
| 2017 | 3.64 | 4.65 | 3.02 |
| 2016 | 4.06 | 5.28 | 2.74 |
| 2015 | 3.55 | 6.7 | 2.3 |
| 2014 | 2.1 | 2.84 | 1.63 |
| 2013 | 1.86 | 2.21 | 1.51 |
| 2012 | 2.24 | 2.8 | 1.7 |
| 2011 | 3.81 | 4.48 | 2.1 |
| 2010 | 4.19 | 5.16 | 3.02 |
| 2009 | 3.63 | 5.05 | 2.12 |
| 2008 | 2.9 | 5.29 | 1.46 |
| 2007 | 4.23 | 6.58 | 1.78 |
| 2006 | 1.85 | 2.32 | 1.22 |
| 2005 | 1.51 | 2.08 | 1.23 |
| 2004 | 2.14 | 3.05 | 1.42 |
| 2003 | 2.7 | 3.95 | 2.09 |
| 2002 | 4.83 | 5.48 | 3.91 |
| 2001 | 6.82 | 8.59 | 4.51 |
| 2000 | 5.8 | 8.6 | 3.38 |
| 1999 | 4.32 | 6.01 | 3.21 |
| 1998 | 6.11 | 7.54 | 3.97 |