Year Percent 1990 1.2 1995 12.4 1997 10.6 1999 10.2 2001 8.9 2002 13.2 2003 8.3 2004 5.7 2005 6.1 2006 7.9 2007 7.8 2008 4.3 2009 5.8 2010 5.5 2011 5 2012 3.3 2013 1.8 2014 2.4 2015 1.9 2016 1.7