| Year | Value | | 2021 | 1,490.5503094539 | | 2020 | 1,171.8488365795 | | 2019 | 1,224.8039422315 | | 2018 | 1,982.943537883 | | 2017 | 903.87257484746 | | 2016 | 1,071.2356761097 | | 2015 | 1,069.7426916644 | | 2014 | 1,055.1233160472 | | 2013 | 1,082.2377293104 | | 2012 | 938.18541738759 | | 2011 | 765.56600136417 | | 2010 | 701.69642257696 | | 2009 | 563.26207608701 | | 2008 | 18.525291626625 | | 2007 | 119.85951941372 | | 2006 | 158.23594613824 | | 2005 | 223.82818771973 | | 2004 | 229.56803140038 | | 2003 | 266.45085833015 | | 2002 | 312.85600528461 | | 2001 | 331.36307299446 | | 2000 | 306.83369153557 | | 1999 | 336.32138954252 | | 1998 | 282.01141372912 | | 1997 | 457.27389712715 | | 1996 | 519.95380699295 | | 1995 | 400.69479972862 | | 1994 | 411.49447090474 | | 1993 | 423.91472977012 | | 1992 | 425.76906717422 | | 1991 | 602.06894955889 | | 1990 | 654.91914170504 | | 1989 | 659.48908743593 | | 1988 | 612.14089188406 | | 1987 | 545.98372013508 | | 1986 | 532.06621441715 | | 1985 | 530.13241674603 | | 1984 | 632.89103925418 | | 1983 | 767.74274895598 | | 1982 | 861.90416762038 | | 1981 | 912.94193308013 | | 1980 | 761.77467013592 | | 1979 | 659.67344775778 | | 1978 | 570.00264598096 | | 1977 | 560.72473575361 | | 1976 | 578.02953206803 |
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