| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.2 | 1.3 | 1.11 |
| 2024 | 1.28 | 1.63 | 0.89 |
| 2023 | 2.65 | 3.74 | 1.61 |
| 2022 | 3.85 | 5.33 | 2.23 |
| 2021 | 6.65 | 10.2 | 3.9 |
| 2020 | 6.29 | 8.28 | 4.04 |
| 2019 | 3.76 | 4.47 | 2.38 |
| 2018 | 4.16 | 6.53 | 2.27 |
| 2017 | 5.51 | 6.8 | 4.07 |
| 2016 | 3.95 | 5.38 | 2.85 |
| 2015 | 5.04 | 7.89 | 3.76 |
| 2014 | 5.12 | 6.48 | 3.37 |
| 2013 | 5.69 | 7.97 | 4.09 |
| 2012 | 4.06 | 4.58 | 3.46 |
| 2011 | 6.99 | 13.02 | 3.51 |
| 2010 | 10.17 | 13.11 | 7.96 |
| 2009 | 6.16 | 8.73 | 4.18 |