Year Percent 1990 77.067 1991 77.304 1992 77.418 1993 77.702 1994 78.133 1995 78.529 1996 78.877 1997 79.196 1998 77.4 1999 75.469 2000 77.447 2001 79.313 2002 81.039 2003 82.627 2004 84.085 2005 84.155 2006 84.241 2007 84.324 2008 84.41 2009 84.503 2010 84.605 2011 84.735 2012 84.854 2013 84.914 2014 84.983 2015 85.047 2016 85.162 2017 85.43 2018 85.697 2019 85.962 2020 86.221 2021 86.474 2022 86.721 2023 86.961 2024 87.196 2025 87.425 2026 87.649 2027 87.869 2028 88.082 2029 88.287 2030 88.484