Year Percent 1984 0.98 1986 3.79 1987 1.15 1989 1.19 1991 1.12 1992 0.93 1993 1.38 1994 0.82 1995 0.47 1996 1.54 1997 1.59 1998 0.83 1999 4.24 2001 1.4 2002 3.74 2003 2.86 2004 3.37 2006 3.69 2007 2.71 2008 3.26 2009 4.67 2010 2.92 2011 3.01 2012 4.38 2013 3.7 2014 3.37 2015 4.16 2016 3.87