Year % (national estimate) 1960 23.641432133889232 1970 26.38274759559819 1980 32.9678215079933 1990 38.482430508242686 1991 41.26685030483299 1992 45.28005449088085 1993 43.55981371824911 1995 44.52162350170211 1996 44.03863658287694 1997 45.41874089099956 1998 45.300104921779145 1999 45.37539464594897 2001 45.55518939470766 2002 47.273298837153824 2003 46.10835033090635 2004 46.15889606479762 2005 46.34258084938382 2006 46.34775603323368 2007 45.99057552602352 2008 45.22564734186552 2009 45.09294441506705 2011 42.88162771959741 2012 42.12216229761572 2013 40.9784954212694 2014 40.15655157360917 2015 40.684441523454666 2016 41.285091575167854 2017 40.923061867768965 2018 41.21004622577556 2019 41.97495418791694 2020 37.95162390602196 2021 41.73567556971507 2022 41.95887798598858 2023 41.350435076874426