Year Index 1980 0.053 1981 0.064 1982 0.075 1983 0.081 1984 0.095 1985 0.161 1986 0.314 1987 1.846 1988 4.708 1989 8.106 1990 13.692 1991 20.553 1992 41.075 1993 51.236 1994 55.455 1995 61.157 1996 66.587 1997 71.746 1998 75.01 1999 75.191 2000 74.923 2001 74.648 2002 75.961 2003 76.925 2004 78.211 2005 77.095 2006 80.25 2007 83.506 2008 92.439 2009 93.167 2010 96.878 2011 101.694 2012 108.387 2013 113.613 2014 115.657 2015 111.381 2016 110.472 2017 115.417 2018 122.421 2019 124.884 2020 127.799 2021 130.751 2022 133.734 2023 136.739 2024 139.875