Year Index 1980 0.324 1981 0.385 1982 0.463 1983 0.523 1984 0.596 1985 0.727 1986 0.899 1987 1.148 1988 1.7 1989 2.014 1990 2.428 1991 3.14 1992 3.892 1993 4.828 1994 6.354 1995 8.109 1996 9.779 1997 12.041 1998 18.582 1999 24.417 2000 26.727 2001 29.766 2002 31.814 2003 33.708 2004 35.727 2005 37.351 2006 43.503 2007 46.085 2008 53.43 2009 58.379 2010 63.777 2011 71.141 2012 79.914 2013 87.639 2014 92.947 2015 100 2016 107.471 2017 110.378 2018 114.765 2019 118.975 2020 124.715 2021 130.991 2022 137.486 2023 144.282 2024 151.414