Year % of children ages 12-23 months 1980 9.747285580951226 1981 17.338761895983595 1982 28.796175137447126 1983 37.097367195521784 1984 43.52583161504408 1985 51.40614396598174 1986 61.597087039475454 1987 65.47930785565609 1988 71.2353378610282 1989 79.34764066112871 1990 82.21329028187571 1991 79.66114337471362 1992 72.86260733558494 1993 79.89204353166794 1994 80.55403217558903 1995 82.07840813005537 1996 79.79877174064396 1997 79.3228281057891 1998 80.19120290358879 1999 80.77456575311031 2000 83.81255288246933 2001 84.13449010533168 2002 82.0303588773696 2003 82.30240059878606 2004 82.94046440369029 2005 83.54770423688699 2006 85.3280374919951 2007 86.54553801408322 2008 87.17141937597675 2009 87.93680641674396 2010 87.51365913752944 2011 86.99701452756094 2012 88.68686299757138 2013 89.15704532427864 2014 88.77739182460171 2015 87.4295140405854 2016 87.53840480271957 2017 88.2268623664445 2018 88.05649224410207 2019 88.13364932529791 2020 83.13446725196269 2021 80.29791413896002 2022 83.81782825933651