Year Percent change 1980 90.227 1981 101.737 1982 100.574 1983 135.02 1984 192.121 1985 226.029 1986 147.137 1987 228.327 1988 629.118 1989 1430.72 1990 2947.73 1991 432.772 1992 951.956 1993 1927.38 1994 2075.83 1995 66.008 1996 15.757 1997 6.926 1998 3.196 1999 4.859 2000 7.044 2001 6.84 2002 8.45 2003 14.714 2004 6.598 2005 6.87 2006 4.184 2007 3.641 2008 5.678 2009 4.888 2010 5.039 2011 6.636 2012 5.404 2013 6.204 2014 6.329 2015 9.03 2016 8.74 2017 3.446 2018 3.665 2019 3.563 2020 4.069 2021 4 2022 3.968 2023 3.968 2024 3.969