Year Percent 1990 82.7 1991 82.731 1992 82.804 1993 82.779 1994 82.895 1995 82.957 1996 83.056 1997 83.148 1998 83.894 1999 82.064 2000 82.692 2001 83.658 2002 83.243 2003 83.254 2004 81.432 2005 81.542 2006 82.221 2007 82.736 2008 85.536 2009 85.845 2010 86.321 2011 85.316 2012 85.717 2013 84.753 2014 83.986 2015 84.586 2016 85.534 2017 85.693 2018 85.853 2019 86.021 2020 86.201 2021 86.386 2022 86.579 2023 86.779 2024 86.985 2025 87.198 2026 87.415 2027 87.641 2028 87.871 2029 88.1 2030 88.323