| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.58 | 3.02 | 2.13 |
| 2024 | 2.23 | 2.87 | 1.88 |
| 2023 | 1.8 | 1.99 | 1.61 |
| 2022 | 1.77 | 1.94 | 1.61 |
| 2021 | 1.69 | 1.98 | 1.32 |
| 2020 | 1.59 | 1.85 | 1.41 |
| 2019 | 1.8 | 2.1 | 1.56 |
| 2018 | 1.8 | 2.03 | 1.53 |
| 2017 | 2.02 | 2.47 | 1.81 |
| 2016 | 1.66 | 2.87 | 1.18 |
| 2015 | 1.54 | 2.12 | 1.24 |
| 2014 | 0.99 | 1.45 | 0.79 |
| 2013 | 0.88 | 1.01 | 0.74 |
| 2012 | 0.95 | 1.08 | 0.85 |
| 2011 | 1.26 | 1.54 | 0.96 |
| 2010 | 1.78 | 2.16 | 1.43 |
| 2009 | 1.81 | 2.2 | 1.41 |
| 2008 | 2.38 | 4.04 | 1.32 |
| 2007 | 3.32 | 5.19 | 1.56 |
| 2006 | 1.38 | 1.6 | 1.17 |
| 2005 | 1.36 | 1.6 | 1.15 |
| 2004 | 1.35 | 2.02 | 1.11 |
| 2003 | 1.84 | 2.22 | 1.57 |
| 2002 | 1.94 | 2.21 | 1.43 |
| 2001 | 2.34 | 3.03 | 1.74 |
| 2000 | 3.61 | 5.17 | 2.28 |
| 1999 | 1.98 | 2.53 | 1.4 |