Year current US$ 1991 5794762.31013081 1992 6009896.40522319 1993 5926359.71882731 1994 5973760.81154519 1995 6103346.45295336 1996 6098618.96202759 1997 9999301.59978972 1998 11090504.8255898 1999 10905951.1170103 2000 10430563.165184 2001 10492086.5971133 2002 10726791.1738169 2003 11402933.5404541 2004 11559025.0141959 2005 12126590.9713549 2006 12535426.4402973 2007 12807049.5940819 2008 12804080.755627 2009 12731147.2714788 2010 12786758.0492098 2011 12719269.4084256 2012 13181924.1230693 2013 13835720.1967511 2014 14668879.4639278 2015 15548417.6520766 2016 15306078.9274015 2017 15031918.2554313 2018 15223693.1242932 2019 15428579.7393455 2020 14518855.9275168 2021 14482894.7545231