Year Percent 1990 73.959 1991 74.048 1992 74.597 1993 74.599 1994 75.286 1995 75.616 1996 76.094 1997 76.656 1998 76.53 1999 76.767 2000 76.72 2001 76.381 2002 75.883 2003 75.646 2004 75.268 2005 75.247 2006 75.458 2007 75.368 2008 75.803 2009 75.644 2010 75.207 2011 74.652 2012 74.494 2013 73.876 2014 73.932 2015 73.691 2016 74.311 2017 74.17 2018 74.029 2019 73.887 2020 73.743 2021 73.598 2022 73.451 2023 73.303 2024 73.155 2025 73.008 2026 72.861 2027 72.714 2028 72.567 2029 72.42 2030 72.272