Year Index 1980 20.685 1981 21.538 1982 24.28 1983 28.016 1984 34.93 1985 43.822 1986 66.741 1987 76.964 1988 86.521 1989 93.783 1990 103.619 1991 115.59 1992 120.498 1993 126.677 1994 133.065 1995 138.44 1996 141.559 1997 141.996 1998 148.782 1999 151.385 2000 151.693 2001 163.932 2002 185.252 2003 217.789 2004 235.407 2005 246.814 2006 247.859 2007 262.78 2008 280.741 2009 288.371 2010 305.063 2011 318.432 2012 334.059 2013 352.684 2014 377.193 2015 402.34 2016 434.025 2017 464.169 2018 494.096 2019 526.1 2020 555.061 2021 582.877 2022 612.086 2023 642.759 2024 674.969