Year Percent 1990 65.546 1991 65.469 1992 65.397 1993 65.342 1994 65.295 1995 65.278 1996 65.239 1997 65.219 1998 65.2 1999 65.191 2000 65.175 2001 65.158 2002 65.156 2003 65.128 2004 65.111 2005 65.101 2006 65.092 2007 65.081 2008 65.097 2009 65.075 2010 65.072 2011 65.086 2012 65.105 2013 65.116 2014 65.118 2015 65.125 2016 65.181 2017 65.226 2018 65.274 2019 65.323 2020 65.372 2021 65.426 2022 65.481 2023 65.537 2024 65.597 2025 65.661 2026 65.733 2027 65.808 2028 65.887 2029 65.968 2030 66.05