Year Percent 1980 101.11279 1981 108.20332 1982 118.80881 1983 147.4915 1984 145.38267 1985 157.03491 1986 144.89394 1987 113.91054 1988 150.692 1989 142.80228 1990 49.09827 1991 68.99042 1992 75.06873 1993 78.30311 1994 88.58029 1995 84.3194 1996 98.56956 1997 88.15954 1998 63.21512 1999 70.08145 2000 86.63675 2001 88.07375 2002 84.08878 2003 87.76053 2004 93.94369 2005 100.89545 2006 112.31662 2007 109.15988 2008 108.93448 2009 76.81866 2010 91.17354 2011 105.87244 2012 110.19128 2013 114.56857 2014 112.78155 2015 108.79527 2016 104.32732 2017 112.80657