| Year | Value | | 2021 | 7,367.8101803544 | | 2020 | 6,318.7133669083 | | 2019 | 7,278.3168222269 | | 2018 | 7,124.2663294496 | | 2017 | 6,739.9627385769 | | 2016 | 6,515.9286279243 | | 2015 | 6,231.531887459 | | 2014 | 5,870.8150115071 | | 2013 | 5,557.4811135089 | | 2012 | 5,540.4013834955 | | 2011 | 5,373.6861042301 | | 2010 | 5,070.4963188643 | | 2009 | 4,617.5474457046 | | 2008 | 4,659.2693329153 | | 2007 | 4,163.790028807 | | 2006 | 3,651.6210183983 | | 2005 | 3,496.3409051084 | | 2004 | 2,113.7561023464 | | 2003 | 2,105.6267864946 | | 2002 | 2,844.773044513 | | 2001 | 2,732.0505187709 | | 2000 | 2,616.8447786336 | | 1999 | 2,428.1723037005 | | 1998 | 2,432.5303804054 | | 1997 | 2,268.2651433087 | | 1996 | 2,088.230280097 | | 1995 | 1,911.4527462168 | | 1994 | 1,727.3225580482 | | 1993 | 1,556.1904672429 | | 1992 | 1,442.9355105705 | | 1991 | 1,232.6039205726 | | 1990 | 901.32164919112 | | 1989 | 863.19056720985 | | 1988 | 695.80511123887 | | 1987 | 785.99176633421 | | 1986 | 855.22961450865 | | 1985 | 699.91619956103 | | 1984 | 1,505.3947795056 | | 1983 | 1,286.0418478841 | | 1982 | 1,219.5845432738 | | 1981 | 1,124.5187010539 | | 1980 | 1,056.9469771379 | | 1979 | 940.69025517386 | | 1978 | 831.06222068942 | | 1977 | 800.56760135725 | | 1976 | 717.93693261846 | | 1975 | 670.98576787525 | | 1974 | 558.40688447305 | | 1973 | 461.11036311669 | | 1972 | 409.31404673154 | | 1971 | 345.87254352194 |
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