Year Percent change 1980 188.57 1981 101.495 1982 131.503 1983 190.692 1984 444.878 1985 185.175 1986 19.653 1987 16.125 1988 16.397 1989 20.692 1990 17.612 1991 18.037 1992 9.37 1993 11.248 1994 14.452 1995 8.104 1996 10.587 1997 6.988 1998 8.622 1999 1.344 2000 0 2001 1.409 2002 6.496 2003 -1.902 2004 1.248 2005 2.343 2006 -0.12 2007 3.498 2008 3.73 2009 3.933 2010 2.703 2011 2.105 2012 1.649 2013 1.826 2014 -0.199 2015 -0.998 2016 -0.202 2017 0.404 2018 0.805 2019 1.284 2020 1.998 2021 1.998 2022 1.998 2023 1.998 2024 1.998