Year Percent 1983 17.89677 1984 15.86564 1985 1.53898 1986 -0.30971 1987 4.51743 1988 18.37399 1989 -2.79209 1990 9.00644 1991 6.11137 1992 8.56597 1993 0.65473 1994 68.22795 1995 -6.97546 1996 4.59005 1997 11.83641 1998 3.41364 1999 2.48182 2000 2.89198 2001 2.42677 2002 2.43395 2003 2.61763 2004 7.01516 2005 0.85608 2006 9.26329 2007 -0.13768 2008 8.60201 2009 2.43784 2010 1.71769 2011 2.31358 2012 3.96016 2013 1.71854 2014 0.29631 2015 2.74197 2016 -1.57541 2017 1.24926