| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.26 | 1.47 | 1.17 |
| 2024 | 1.24 | 1.62 | 1.03 |
| 2023 | 1.39 | 1.47 | 1.29 |
| 2022 | 1.54 | 2.08 | 1.35 |
| 2021 | 1.57 | 2.03 | 1.37 |
| 2020 | 1.82 | 2.15 | 1.64 |
| 2019 | 1.72 | 2.13 | 1.51 |
| 2018 | 2.06 | 2.66 | 1.5 |
| 2017 | 2.76 | 3.17 | 2.4 |
| 2016 | 3.25 | 4.72 | 2.88 |
| 2015 | 4.56 | 6.05 | 3.11 |
| 2014 | 3.93 | 4.98 | 3.25 |
| 2013 | 4.66 | 5.68 | 3.6 |
| 2012 | 4.45 | 5.89 | 3.09 |
| 2011 | 12.36 | 18.4 | 4.72 |
| 2010 | 14.81 | 19.65 | 8.54 |
| 2009 | 8.02 | 14.35 | 3.33 |
| 2008 | 5.19 | 13.18 | 1.86 |
| 2007 | 8.63 | 13.68 | 2.62 |
| 2006 | 2.41 | 3.32 | 1.27 |
| 2005 | 1.61 | 2.06 | 1.22 |
| 2004 | 2.42 | 3.38 | 1.75 |
| 2003 | 3 | 4.21 | 2.06 |
| 2002 | 4.97 | 5.5 | 4.36 |
| 2001 | 5.9 | 6.92 | 4.29 |