Year Total 1985 33175000000 1986 36282000000 1987 37453000000 1988 38150000000 1989 38489000000.00001 1990 39526000000 1991 38735000000 1992 37595000000 1993 33369000000 1994 31397000000 1995 24918000000 1996 23728000000 1997 26100000000 1998 23500000000 1999 26500000000 2000 26100000000 2001 25042000000 2002 26455000000 2003 26627000000 2004 31211000000 2005 30961000000 2006 31811000000 2007 31829000000 2008 35054000000 2009 30405000000 2010 34890000000 2011 32203000000 2012 30794000000 2013 31507000000 2014 34736999999.99999 2015 34082000000 2016 33100000000