Year Percent 1990 69.923 1991 69.698 1992 69.497 1993 69.522 1994 69.508 1995 71.232 1996 72.873 1997 74.43 1998 75.903 1999 77.297 2000 78.9 2001 80.419 2002 81.851 2003 83.193 2004 84.444 2005 85.606 2006 85.564 2007 85.515 2008 85.461 2009 85.402 2010 85.344 2011 85.29 2012 85.237 2013 85.183 2014 85.686 2015 86.176 2016 86.579 2017 86.783 2018 86.985 2019 87.185 2020 87.384 2021 87.583 2022 87.779 2023 87.975 2024 88.172 2025 88.371 2026 88.573 2027 88.778 2028 88.983 2029 89.185 2030 89.38