Year % of cohort 1973 98.1157073974609 1974 98.4154663085938 1975 96.1505966186523 1976 99.085823059082 1977 98.6691284179688 1978 98.9775695800781 1979 99.0156478881836 1980 99.4392700195312 1981 99.2721176147461 1984 99.1124572753906 1985 99.5279083251953 1986 98.5123825073242 1987 99.7621383666992 1988 99.7126007080078 1989 97.3759994506836 1990 98.6558837890625 1991 99.1235809326172 1992 97.7569580078125 1998 99.5468673706055 1999 99.6602401733398 2000 98.8239212036133 2001 98.326042175293 2002 99.7807693481445 2003 98.6819915771484 2004 99.8569793701172 2005 98.9011535644531 2006 100 2007 98.7686614990234 2008 99.8917388916016 2009 99.3346633911133 2010 99.4931488037109 2011 97.3899536132812 2013 99.3929214477539 2014 99.4233322143555 2015 99.6096267700195 2016 99.3833389282227 2017 99.2849807739258 2018 99.320671081543 2019 98.6229476928711 2020 99.1035232543945