Year Percent 1990 79.314 1991 79.435 1992 79.722 1993 79.104 1994 78.305 1995 77.351 1996 75.841 1997 74.613 1998 73.715 1999 73.206 2000 75.604 2001 74.872 2002 74.403 2003 74.171 2004 74.047 2005 73.971 2006 73.495 2007 73.686 2008 73.631 2009 73.596 2010 74.397 2011 75.327 2012 76.946 2013 78.416 2014 78.846 2015 79.154 2016 79.322 2017 79.486 2018 79.714 2019 79.97 2020 80.207 2021 79.687 2022 79.159 2023 78.646 2024 78.168 2025 77.723 2026 77.042 2027 76.407 2028 75.826 2029 75.293 2030 74.795