Year Number 1996 82.5 1998 79.1044769287109 2000 85.0746231079102 2002 82.0895538330078 2003 85.572135925293 2004 88.461540222168 2005 88.461540222168 2006 86.538459777832 2007 85.0961532592773 2008 85.5769195556641 2009 87.2037887573242 2010 88.6255950927734 2011 89.6713638305664 2012 90.1408462524414 2013 89.6713638305664 2014 84.7290649414063 2015 84.2364501953125 2016 84.7290649414063 2017 85.2216720581055 2018 87.3786392211914 2019 81.159423828125 2020 81.6425094604492 2021 87.4396133422852 2022 83.5748825073242