Year % of children ages 12-23 months 1982 3 1983 6 1984 8 1985 21 1986 26 1987 23 1988 59 1989 31 1990 31 1991 35 1992 39 1993 44 1994 48 1995 49 1996 50 1997 52 1998 53 1999 54 2000 55 2001 55 2002 56 2003 57 2004 57 2005 58 2006 59 2007 60 2008 62 2009 63 2010 64 2011 65 2012 66 2013 68 2014 69 2015 69 2016 69 2017 69 2018 69 2019 65 2020 65 2021 65 2022 65