Year Total 1985 19249000000 1986 21419000000 1987 23754000000 1988 25508000000 1989 27363000000 1990 28960000000 1991 31889000000 1992 35076000000 1993 35946999999.99999 1994 26741000000 1995 27916000000 1996 28440000000 1997 28943000000 1998 31134000000 1999 29496000000 2000 31329000000 2001 32429000000 2002 34312000000 2003 35506000000 2004 37129000000 2005 38448000000 2006 38611999999.99999 2007 38948000000 2008 37990000000 2009 38728000000 2010 38292000000 2011 39026000000 2012 38751999999.99999 2013 39063000000 2014 39803000000.00001 2015 37977000000 2016 38205000000