| Year | Value | | 2021 | 15,098.239663879 | | 2020 | 13,333.543284685 | | 2019 | 13,241.25660211 | | 2018 | 13,050.242229784 | | 2017 | 11,609.618130567 | | 2016 | 10,405.661261776 | | 2015 | 10,613.080624815 | | 2014 | 11,957.209040355 | | 2013 | 11,445.939399934 | | 2012 | 11,004.725188487 | | 2011 | 11,566.237159988 | | 2010 | 10,519.151772036 | | 2009 | 9,791.8521223465 | | 2008 | 11,941.317446389 | | 2007 | 9,386.707870953 | | 2006 | 7,543.1085229202 | | 2005 | 6,747.0533364491 | | 2004 | 5,524.9642487697 | | 2003 | 4,815.2635539829 | | 2002 | 4,438.6137647209 | | 2001 | 4,251.6267733898 | | 2000 | 3,847.901057656 | | 1999 | 3,746.8954268361 | | 1998 | 3,847.934265017 | | 1997 | 3,499.5558486149 | | 1996 | 3,508.2896691138 | | 1995 | 3,089.8754295461 | | 1994 | 2,282.4014792442 | | 1993 | 1,756.5388359568 | | 1992 | 1,526.9561602501 | | 1991 | 1,311.3342369668 | | 1990 | 977.07433369754 |
|