Year % of cohort 1960 57.573293 1961 57.724409 1962 57.12234 1963 58.055155 1964 59.245147 1965 58.145043 1966 57.920335 1967 57.292222 1968 56.75108 1969 55.388161 1970 55.635114 1971 55.542252 1972 55.597068 1973 55.708344 1974 55.439005 1975 54.263164 1976 53.667128 1977 53.263613 1978 52.827015 1979 51.814074 1980 51.45919 1981 51.990248 1982 52.793211 1983 52.295673 1984 51.192241 1985 52.946212 1986 57.483934 1987 57.359144 1988 56.800544 1989 56.035793 1990 54.787965 1991 54.103995 1992 51.25147 1993 44.31405 1994 41.001747 1995 41.493079 1996 45.014694 1997 47.851744 1998 48.782835 1999 45.266003 2000 43.586526 2001 43.522721 2002 42.433187 2003 42.265147 2004 43.528474 2005 43.669476 2006 47.006687 2007 49.334238 2008 49.804855 2009 51.595935 2010 51.988721 2011 54.246817 2012 55.538146 2013 56.774378 2014 57.517464 2015 59.171433 2016 60.792585 2017 63.004934 2018 63.566095 2019 64.816353 2020 59.477717 2021 53.849123 2022 55.001426