Year Percent 1990 65.21 1991 64.897 1992 64.577 1993 64.463 1994 64.316 1995 63.601 1996 62.925 1997 62.389 1998 63.112 1999 63.818 2000 64.49 2001 64.591 2002 64.62 2003 64.583 2004 64.492 2005 64.361 2006 64.274 2007 64.149 2008 64.009 2009 63.888 2010 63.81 2011 63.943 2012 64.138 2013 64.385 2014 64.67 2015 64.586 2016 64.811 2017 65.19 2018 65.572 2019 65.937 2020 66.273 2021 66.569 2022 66.839 2023 67.07 2024 67.244 2025 67.354 2026 67.398 2027 67.384 2028 67.342 2029 67.315 2030 67.324