Year Index 1980 5.935 1981 5.809 1982 5.814 1983 5.809 1984 5.623 1985 5.83 1986 5.694 1987 5.695 1988 5.693 1989 5.695 1990 5.695 1991 7.717 1992 26.987 1993 57.977 1994 79.443 1995 87.259 1996 100 1997 111.245 1998 118.733 1999 121.229 2000 128.076 2001 132.957 2002 137.806 2003 144.97 2004 149.54 2005 154.485 2006 158.314 2007 165.258 2008 172.062 2009 176.223 2010 184.141 2011 188.404 2012 190.368 2013 191.179 2014 193.414 2015 194.5 2016 193.738 2017 196.421 2018 200.502 2019 204.951 2020 210.075 2021 216.149 2022 222.988 2023 229.982 2024 237.16