| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2024 | 2.49 | 3.34 | 1.99 |
| 2023 | 4.35 | 5.3 | 3.21 |
| 2022 | 2.63 | 4.66 | 1.65 |
| 2021 | 1.61 | 2.17 | 1.29 |
| 2020 | 1.23 | 1.59 | 0.97 |
| 2019 | 1.48 | 2.14 | 1.18 |
| 2018 | 1.7 | 2.28 | 1.19 |
| 2017 | 1.98 | 2.24 | 1.78 |
| 2016 | 2.27 | 2.85 | 1.77 |
| 2015 | 3.47 | 5.99 | 2.21 |
| 2014 | 1.45 | 2.83 | 1 |
| 2013 | 1.42 | 1.77 | 1.1 |
| 2012 | 2 | 2.43 | 1.39 |
| 2011 | 3.68 | 5.15 | 1.92 |
| 2010 | 23.77 | 50.21 | 4.69 |
| 2009 | 47.13 | 55.64 | 38.69 |
| 2008 | 17.91 | 43.76 | 5.36 |
| 2007 | 15.16 | 35.03 | 3.57 |
| 2006 | 2.67 | 3.76 | 1.87 |
| 2005 | 1.74 | 2.37 | 1.21 |
| 2004 | 2.82 | 3.81 | 2.1 |
| 2003 | 2.6 | 3.2 | 2.21 |
| 2002 | 2.94 | 3.73 | 1.98 |
| 2001 | 2.83 | 3.39 | 2.2 |
| 2000 | 2.61 | 3.21 | 2 |
| 1999 | 2.17 | 3 | 1.49 |
| 1998 | 2.01 | 2.5 | 1.58 |