| Year | Value | | 2021 | 14,591.582025946 | | 2020 | 13,661.846748421 | | 2019 | 15,768.94029079 | | 2018 | 16,444.154738487 | | 2017 | 16,557.208783554 | | 2016 | 14,949.304682776 | | 2015 | 14,048.435557981 | | 2014 | 14,854.510423791 | | 2013 | 15,207.282794932 | | 2012 | 13,326.152591336 | | 2011 | 13,238.78577697 | | 2010 | 11,194.051413349 | | 2009 | 8,875.7513810538 | | 2008 | 8,641.749363885 | | 2007 | 6,737.0562656402 | | 2006 | 5,629.8462516583 | | 2005 | 4,959.2523448049 | | 2004 | 3,839.9167057669 | | 2003 | 3,380.4651948118 | | 2002 | 4,010.6848494932 | | 2001 | 6,155.1391212043 | | 2000 | 6,755.6776711388 | | 1999 | 7,160.8461800893 | | 1998 | 7,622.5254174475 | | 1997 | 7,243.3831402064 | | 1996 | 6,212.5617583929 | | 1995 | 5,852.5636689817 | | 1994 | 5,346.2542386385 | | 1993 | 4,610.7687820728 | | 1992 | 3,975.5978184104 | | 1991 | 3,438.2831375634 | | 1990 | 2,819.5458968935 | | 1989 | 2,569.8004184801 | | 1988 | 2,527.8358705707 | | 1987 | 2,282.2596655031 | | 1986 | 1,794.2966845111 | | 1985 | 1,392.1902840794 | | 1984 | 1,428.7961801143 | | 1983 | 1,536.8541400037 | | 1982 | 2,845.6453949048 | | 1981 | 3,502.2809156682 | | 1980 | 3,115.898408633 | | 1979 | 2,283.3813200381 | | 1978 | 1,555.8360184588 | | 1977 | 1,312.3598730039 | | 1976 | 1,173.858388689 | | 1975 | 1,142.4705995261 | | 1974 | 1,359.7754772066 | | 1973 | 1,247.8303842228 | | 1972 | 736.28455951692 | | 1971 | 954.97980418662 |
|