Year Percent 1990 10.587 1991 10.93 1992 11.305 1993 11.641 1994 11.983 1995 12.336 1996 12.397 1997 12.465 1998 12.536 1999 12.614 2000 12.707 2001 12.298 2002 12.903 2003 11.902 2004 12.049 2005 12.201 2006 12.543 2007 15.157 2008 14.753 2009 15.504 2010 15.289 2011 15.226 2012 14.833 2013 13.864 2014 13.869 2015 13.894 2016 13.896 2017 13.959 2018 14.018 2019 14.071 2020 14.117 2021 14.155 2022 14.187 2023 14.213 2024 14.234 2025 14.251 2026 14.269 2027 14.285 2028 14.301 2029 14.321 2030 14.348