年份 | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 |
P(x) | 0.0112 | 0.0978 | 0.1765 | 0.3664 | 0.4482 | 0.5388 | 0.6067 | 0.6507 | 0.6327 | 0.6924 | 0.4800 | 0.6903 | 0.8566 | 0.8973 |