| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2023 | 21.62 | 23.7 | 18.25 |
| 2022 | 20.31 | 25.17 | 16.36 |
| 2021 | 27.94 | 39.62 | 17.78 |
| 2020 | 34.86 | 41.11 | 28.5 |
| 2019 | 33.34 | 40.65 | 26.05 |
| 2018 | 28.93 | 33 | 24.33 |
| 2017 | 25.73 | 29.62 | 20.93 |
| 2016 | 23.06 | 28.29 | 18.79 |
| 2015 | 20.28 | 27.92 | 15.79 |
| 2014 | 15.16 | 17.26 | 12.74 |
| 2013 | 16.04 | 18.17 | 13.87 |
| 2012 | 16.97 | 21.59 | 12.66 |
| 2011 | 29.31 | 39.16 | 20.19 |
| 2010 | 32.27 | 38.16 | 27.88 |
| 2009 | 28.53 | 35.22 | 23.56 |
| 2008 | 41.79 | 87.79 | 18.71 |
| 2007 | 56.72 | 76.03 | 37.1 |
| 2006 | 27.73 | 39.11 | 16.37 |
| 2005 | 20.18 | 24.82 | 16.04 |