Year % of children ages 12-23 months 1980 9.153773577476429 1981 16.915138646469057 1982 19.590345003424847 1983 31.517068976853746 1984 35.45395648091137 1985 40.38113979104441 1986 45.25208288790891 1987 49.18869841225156 1988 52.65272708798267 1989 57.26622469405045 1990 59.23386172576529 1991 53.852713735277874 1992 53.90161048438653 1993 56.312637876024596 1994 61.13673400356401 1995 58.08466672955992 1996 59.76517876997769 1997 59.046837720924856 1998 56.99229807985145 1999 53.58816537070962 2000 57.68749497228199 2001 58.06295489854391 2002 59.99886996155457 2003 61.63824097022404 2004 63.424009942645064 2005 63.56066769174469 2006 66.56850784247479 2007 70.2068405817474 2008 70.69561863232491 2009 73.38480914703534 2010 75.93223731618738 2011 76.17639582816066 2012 77.14324110349799 2013 75.81365992265404 2014 76.11734278790631 2015 74.96538759574099 2016 73.32425891429807 2017 74.01455911743928 2018 74.07487103228081 2019 74.86177551699292 2020 73.24550100368235 2021 69.44770462332603 2022 70.70080826683699