| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.21 | 1.35 | 1.14 |
| 2024 | 1.46 | 2.24 | 1.02 |
| 2023 | 2.36 | 3.1 | 1.93 |
| 2022 | 2.56 | 2.92 | 2.18 |
| 2021 | 2.6 | 3.29 | 2.07 |
| 2020 | 3.13 | 4.63 | 2.16 |
| 2019 | 2.33 | 3.69 | 1.59 |
| 2018 | 2.16 | 2.76 | 1.58 |
| 2017 | 2.49 | 2.96 | 2.11 |
| 2016 | 2.71 | 3.25 | 2.08 |
| 2015 | 3.18 | 5.71 | 2.45 |
| 2014 | 2.42 | 3.25 | 1.98 |
| 2013 | 2.59 | 3.24 | 2.08 |
| 2012 | 3.26 | 4.43 | 2.04 |
| 2011 | 5.45 | 7.04 | 3.95 |
| 2010 | 7.21 | 8.22 | 6.15 |
| 2009 | 6.48 | 8.36 | 4.16 |
| 2008 | 6.31 | 13.02 | 2.66 |
| 2007 | 8.86 | 14.06 | 4.82 |
| 2006 | 2.93 | 4.82 | 1.44 |
| 2005 | 2.06 | 2.71 | 1.37 |
| 2004 | 2.9 | 3.9 | 2.28 |
| 2003 | 3.03 | 4.14 | 2.07 |
| 2002 | 4.75 | 5.36 | 4.09 |
| 2001 | 5.6 | 6.51 | 4 |
| 2000 | 5.09 | 6.61 | 3.5 |