Year Percent 1981 -1.1365 1982 -2.48203 1983 -4.0679 1984 -2.93502 1985 -2.78781 1986 0.79195 1987 -0.80101 1988 -3.57855 1989 -2.42499 1990 -1.90253 1991 4.39848 1992 3.79172 1993 -4.49824 1994 -1.22916 1995 0.84605 1996 0.0995 1997 1.10919 1998 0.34944 1999 0.72803 2000 1.24634 2001 -0.61888 2002 3.26389 2003 2.96008 2004 11.00153 2005 1.37047 2006 5.8472 2007 5.37757 2008 1.36034 2009 -1.1432 2010 4.2763 2011 3.0778 2012 2.81964 2013 3.21722 2014 3.90832 2015 3.7196 2016 -1.49899 2017 -2.88828