| Year | Value | | 2021 | 1,294.48671 | | 2020 | 1,209.70683 | | 2019 | 1,521.14944 | | 2018 | 1,845.64776 | | 2017 | 1,736.549227 | | 2016 | 1,513.832873341 | | 2015 | 1,493.939 | | 2014 | 1,596.774 | | 2013 | 1,637.382 | | 2012 | 1,363.447091 | | 2011 | 1,294.49545 | | 2010 | 1,302.474647875 | | 2009 | 1,782.3 | | 2008 | 1,807.062 | | 2007 | 1,477.828 | | 2006 | 1,412.26 | | 2005 | 1,530.675 | | 2004 | 1,499.485 | | 2003 | 1,478.37 | | 2002 | 1,539.738 | | 2001 | 1,467.445 | | 2000 | 1,727.901 | | 1999 | 1,462.9000244141 | | 1998 | 1,642.8000488281 | | 1997 | 1,789.9000244141 | | 1996 | 1,644.8000488281 | | 1995 | 1,581.9000244141 | | 1994 | 1,468.5 | | 1993 | 1,284.3000488281 | | 1992 | 1,143.3000488281 | | 1991 | 1,005.299987793 | | 1990 | 1,082 | | 1989 | 1,147.9000244141 | | 1988 | 975.799987793 | | 1987 | 1,013.700012207 | | 1986 | 1,014.4000244141 | | 1985 | 909.200012207 | | 1984 | 831.700012207 | | 1983 | 692.0999755859 | | 1982 | 734.700012207 | | 1981 | 644.9000244141 | | 1980 | 588.200012207 | | 1979 | 570.5 | | 1978 | 571.299987793 | | 1977 | 499.299987793 | | 1976 | 471.6000061035 | | 1975 | 460.5 | | 1974 | 407.1000061035 | | 1973 | 316.700012207 | | 1972 | 254.3000030518 | | 1971 | 180.1999969482 | | 1970 | 164.1000061035 |
|