| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2024 | 1.23 | 1.75 | 0.84 |
| 2023 | 1.18 | 1.48 | 1 |
| 2022 | 1.53 | 1.99 | 1.2 |
| 2021 | 1.92 | 2.36 | 1.62 |
| 2020 | 2.02 | 2.56 | 1.57 |
| 2019 | 1.39 | 1.78 | 1.04 |
| 2018 | 1.62 | 2.44 | 1 |
| 2017 | 1.54 | 1.99 | 1.23 |
| 2016 | 1.9 | 2.19 | 1.48 |
| 2015 | 1.68 | 2.47 | 1.18 |
| 2014 | 1.46 | 1.71 | 1.24 |
| 2013 | 1.76 | 2.06 | 1.5 |
| 2012 | 2.22 | 2.69 | 1.57 |
| 2011 | 3.58 | 4.97 | 2.12 |
| 2010 | 5.08 | 7.43 | 3.3 |
| 2009 | 6.02 | 8.16 | 4.08 |
| 2008 | 8.72 | 14.13 | 2.95 |
| 2007 | 5.45 | 11.16 | 2.49 |
| 2006 | 2.95 | 4 | 2.32 |
| 2005 | 2.89 | 3.65 | 2.04 |
| 2004 | 3.62 | 4.71 | 2.35 |
| 2003 | 4.89 | 6.19 | 3.51 |
| 2002 | 5.91 | 6.82 | 4.51 |
| 2001 | 7.43 | 9.19 | 4.9 |
| 2000 | 6.4 | 9.09 | 4.29 |