Year Percent 1989 -42.62355 1990 25.29681 1991 35.71803 1992 1.9299 1993 4.08435 1994 5.32413 1995 4.47146 1996 3.85041 1997 -2.97272 1998 2.88468 1999 -1.79949 2000 -1.12175 2001 0.02251 2002 -1.36922 2003 -1.75888 2004 1.47784 2005 -0.45223 2006 -0.2081 2007 8.57039 2008 9.81332 2009 8.15736 2010 4.20152 2011 -4.60785 2012 -4.05514 2013 -4.36099 2014 -3.95306 2015 -3.4607 2016 -0.63528 2017 0.75128