Year Percent 1990 8.616 1991 3.604 1992 1.461 1993 1.763 1994 4.118 1995 4.764 1996 3.366 1997 4.835 1998 8.225 1999 5.227 2000 5.571 2001 5.887 2002 6.22 2003 6.571 2004 6.939 2005 7.327 2006 7.735 2007 8.163 2008 8.613 2009 9.085 2010 9.581 2011 10.1 2012 9.3 2013 10.9 2014 9.93 2015 12.026 2016 14.368 2017 14.477 2018 14.585 2019 14.694 2020 14.802 2021 14.911 2022 15.019 2023 15.128 2024 15.236 2025 15.345 2026 15.453 2027 15.562 2028 15.67 2029 15.779 2030 15.887