Year Percent 1989 0.21347 1990 1.59149 1991 2.81358 1992 1.05929 1993 1.55356 1994 7.87647 1995 4.33265 1997 5.69624 1998 1.96421 1999 5.71286 2000 5.76547 2001 7.04655 2002 3.2997 2003 1.78207 2004 1.90432 2005 1.59605 2006 1.2307 2007 1.12756 2008 0.91678 2009 1.41337 2010 2.86199 2011 2.51303 2012 2.25436 2013 1.59561 2014 1.55239 2015 1.81774 2016 1.91919