Year Percent 1990 6.256 1991 6.301 1992 6.28 1993 6.412 1994 6.422 1995 6.518 1996 6.713 1997 6.865 1998 7.273 1999 7.662 2000 7.732 2001 7.875 2002 8.127 2003 8.282 2004 8.167 2005 8.205 2006 8.489 2007 8.589 2008 8.825 2009 9.134 2010 8.96 2011 8.655 2012 8.482 2013 8.534 2014 8.64 2015 8.49 2016 7.92 2017 8.003 2018 8.085 2019 8.168 2020 8.25 2021 8.333 2022 8.416 2023 8.498 2024 8.581 2025 8.664 2026 8.746 2027 8.829 2028 8.911 2029 8.994 2030 9.077