Year % of children ages 12-23 months 1980 20.94510629104835 1981 23.168667932549802 1982 28.018961392685295 1983 31.995240793518064 1984 41.21591821518063 1985 57.44178938503943 1986 63.284910358804915 1987 66.9924917896191 1988 72.58369506964287 1989 79.81322739211761 1990 80.89090036822863 1991 74.63207582413763 1992 75.16334328970866 1993 75.93599054570834 1994 74.03694721762251 1995 76.85267815236574 1996 78.51008298581817 1997 76.93251343468978 1998 79.16945242463277 1999 81.70386384006417 2000 83.31138458753531 2001 84.3966779878028 2002 82.34004905222598 2003 82.62406263812028 2004 83.4841079978292 2005 84.22831346026476 2006 83.52678634279549 2007 84.98413138929827 2008 85.87435938203633 2009 86.75694093655085 2010 87.60442054777754 2011 87.38416048944384 2012 83.89157202275261 2013 85.55493475065059 2014 85.28067438883416 2015 84.27935507576717 2016 85.17216811673913 2017 86.25760984125624 2018 85.91658890169985 2019 86.18094062817896 2020 82.96268837016731 2021 82.57827311144189 2022 84.19782897955616