Year Percent 1990 61.897 1991 61.655 1992 61.774 1993 61.656 1994 62.821 1995 64.061 1996 64.334 1997 64.116 1998 64.208 1999 64.241 2000 65.338 2001 66.015 2002 66.243 2003 67.093 2004 66.789 2005 68.225 2006 68.883 2007 69.44 2008 69.967 2009 70.121 2010 69.954 2011 70.422 2012 70.324 2013 70.394 2014 70.51 2015 71.236 2016 71.609 2017 71.784 2018 71.954 2019 72.126 2020 72.302 2021 72.473 2022 72.642 2023 72.815 2024 72.997 2025 73.194 2026 73.395 2027 73.611 2028 73.835 2029 74.057 2030 74.269