Year Index 1980 1.003 1981 1.055 1982 1.175 1983 1.391 1984 1.793 1985 2.205 1986 2.385 1987 2.498 1988 3.1 1989 3.558 1990 5.413 1991 8.289 1992 15.485 1993 20.944 1994 27.328 1995 33.651 1996 39.899 1997 43.955 1998 48.051 1999 51.408 2000 56.908 2001 61.39 2002 67.846 2003 75.733 2004 85.47 2005 95.273 2006 103.703 2007 115.429 2008 131.074 2009 144.922 2010 159.105 2011 168.841 2012 179.736 2013 195.443 2014 209.234 2015 223.302 2016 233.46 2017 249.887 2018 259.539 2019 269.039 2020 281.432 2021 295.454 2022 310.227 2023 325.738 2024 342.025