| Year | Value | | 2014 | 3,513.9549720407 | | 2013 | 3,571.1655633246 | | 2012 | 3,704.4332872078 | | 2011 | 3,909.0830924262 | | 2010 | 3,601.4528438874 | | 2009 | 3,452.0408198097 | | 2008 | 3,712.9353783139 | | 2007 | 3,660.2809118797 | | 2006 | 3,488.8257586897 | | 2005 | 3,413.1050074748 | | 2004 | 3,181.2349449754 | | 2003 | 3,149.8347372893 | | 2002 | 2,794.8322828374 | | 2001 | 2,811.9566638262 | | 2000 | 2,907.6911688504 | | 1999 | 2,866.4318129314 | | 1998 | 3,078.4205212095 | | 1997 | 2,999.1952401485 | | 1996 | 2,913.9124652873 | | 1995 | 2,796.4217092649 | | 1994 | 2,707.7496723764 | | 1993 | 2,597.034493085 | | 1992 | 2,923.6534965161 | | 1991 | 2,650.3840061747 | | 1990 | 2,604.9641566716 |
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