Year % of children ages 12-23 months 1980 6.4106642246444245 1981 10.312716240891369 1982 12.785703326364407 1983 14.592996393830798 1984 16.401828830739916 1985 21.157110943609315 1986 28.36581261871667 1987 31.400508074656695 1988 38.631346522487064 1989 50.289442290202764 1990 56.74348628724824 1991 52.63078102427422 1992 52.781966840316485 1993 55.39107825108415 1994 59.802647478356576 1995 59.53360933265422 1996 59.330931967186 1997 58.80633500801224 1998 57.666209886410606 1999 58.40419139445965 2000 61.01041319716043 2001 61.17376353437927 2002 62.365101486412875 2003 65.24295812824931 2004 67.98148089417519 2005 70.73308301914082 2006 71.37253233366918 2007 73.55535581728284 2008 73.69884260312169 2009 76.45309422674252 2010 77.28977027748027 2011 77.53742587861899 2012 76.79522488377174 2013 76.0794333324726 2014 76.12815773421345 2015 76.12251985175035 2016 75.8094809238422 2017 76.93559705373464 2018 76.98245575093539 2019 76.97432609834257 2020 75.54722265415568 2021 72.33987388295421 2022 73.53686378011716