| Year | Value | | 2021 | 5,262.9135962039 | | 2020 | 4,322.5496753333 | | 2019 | 4,361.9992929296 | | 2018 | 4,340.9198540572 | | 2017 | 3,729.9682187209 | | 2016 | 3,467.3475701546 | | 2015 | 3,277.7882434223 | | 2014 | 3,844.2771410145 | | 2013 | 3,757.6969462432 | | 2012 | 3,522.3728571434 | | 2011 | 3,753.9654854871 | | 2010 | 3,509.842739338 | | 2009 | 3,517.6091529858 | | 2008 | 3,830.3409272825 | | 2007 | 3,229.9772015364 | | 2006 | 2,742.9336107388 | | 2005 | 2,437.801549599 | | 2004 | 2,171.0444204537 | | 2003 | 1,699.3924893249 | | 2002 | 1,308.2165516482 | | 2001 | 1,186.7433826812 | | 2000 | 1,038.9566857387 | | 1999 | 949.09715932971 | | 1998 | 749.07278640427 | | 1997 | 643.21589462086 | | 1996 | 914.57303788651 | | 1995 | 669.04364954681 | | 1994 | 508.952316438 | | 1993 | 316.12843213012 | | 1992 | 136.05456779476 | | 1991 | 250.88316759947 | | 1990 | 491.20782806579 | | 1989 | 560.43266836394 | | 1988 | 520.80485644553 | | 1987 | 550.38988848056 | | 1986 | 571.54543136237 | | 1985 | 511.13751559466 | | 1984 | 511.60486399445 |
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