Year % of children ages 12-23 months 1980 36 1981 27 1982 28 1983 29 1984 34 1985 39 1986 80 1987 80 1988 69 1989 58 1990 69 1991 71 1992 73 1993 75 1994 74 1995 72 1996 72 1997 73 1998 75 1999 83 2000 78 2001 72 2002 82 2003 79 2004 79 2005 87 2006 89 2007 85 2008 82 2009 82 2010 88 2011 84 2012 85 2013 83 2014 91 2015 85 2016 87 2017 84 2018 87 2019 89 2020 82 2021 84 2022 88