Year Percent 1975 -2.49609 1976 3.8051 1977 3.04199 1978 4.37641 1979 7.40813 1980 3.979 1981 -2.24344 1982 -5.1851 1983 0.23268 1984 3.32597 1985 0.81123 1986 4.76759 1987 2.25151 1988 3.13328 1989 3.22826 1990 -3.64019 1991 -4.2314 1992 -7.32243 1993 0.85188 1994 3.43593 1995 1.63659 1996 3.61559 1997 4.30661 1998 3.31105 1999 0.03711 2000 1.94933 2001 -2.70215 2002 0.50556 2003 1.9072 2004 1.0907 2005 3.65157 2006 5.30416 2007 1.39044 2008 -0.32196 2009 -4.3968 2010 -0.09428 2011 0.32964 2012 -0.0505 2013 -0.32707 2014 -0.30912 2015 0.60463 2016 1.7212 2017 1.41379