Year % (national estimate) 1992 49.598112365623464 1995 44.920820898910705 1996 43.23726765759575 1997 40.3013694870085 1998 40.820578107364824 1999 39.626408921506545 2000 39.102584961471045 2001 39.09412302002601 2002 37.108678747089584 2003 35.223428447120284 2004 34.64182884981954 2005 33.35073150557341 2006 32.570396367082395 2007 31.98190774182822 2008 31.9789480478982 2009 32.12732129030442 2010 32.37379135952451 2011 31.36886133571104 2012 31.633771219368953 2013 31.598909513532757 2014 32.12432785159083 2015 32.189299350536835 2016 32.372326705022154 2017 33.05397486358584 2018 32.6498406009737 2019 32.40568844963025 2020 30.444260636693638 2021 29.361547877161055 2022 29.495827797379647 2023 29.477129401041882