Year Percent 1980 0.02555 1981 -0.02309 1982 0 1983 0.04639 1984 0 1985 0.01625 1986 0.00686 1987 -0.00656 1988 -0.24727 1989 0.02742 1990 0.02694 1991 0.03439 1992 0.05946 1993 0.05966 1994 0.42389 1995 0.05789 1996 0.09902 1997 0.12609 1998 0.20893 1999 0.0581 2000 0.09994 2005 0.79028 2006 0.20931 2007 6.47361 2008 3.17322 2009 3.28694 2010 1.48908 2011 6.02504 2012 0.98489 2013 4.03639 2014 3.27233 2015 2.4437 2016 5.18322 2017 1.01117