Year Index 1980 3.508 1981 3.894 1982 4.206 1983 4.427 1984 5.532 1985 5.226 1986 5.458 1987 5.73 1988 6.037 1989 6.761 1990 7.487 1991 8.111 1992 8.397 1993 9.701 1994 10.978 1995 13.082 1996 17.972 1997 22.754 1998 22.478 1999 27.205 2000 31.039 2001 32.183 2002 33.239 2003 36.846 2004 41.292 2005 41.736 2006 45.493 2007 52.178 2008 65.574 2009 68.609 2010 71.409 2011 82.017 2012 91.728 2013 100 2014 103.745 2015 111.144 2016 121.7 2017 134.535 2018 141.686 2019 154.401 2020 168.258 2021 183.357 2022 199.812 2023 217.744 2024 237.285