Year current US$ 1990 3271751.72746758 1991 3714683.51764404 1992 4018782.33599189 1993 4206607.05013843 1994 4246668.88491245 1995 4891885.19205706 1996 4775190.70685088 1997 5463513.15564041 1998 6676468.45032506 1999 6922892.92789412 2000 6867796.16545742 2001 7374599.54799734 2002 8061104.89296099 2003 8615281.9055557 2004 8824974.48009792 2005 10004486.0469342 2006 10545229.3729141 2007 12104026.5913051 2008 12613737.6173977 2009 12980214.1498498 2010 14860685.6038691 2011 14317625.4714982 2012 15535024.2701341 2013 18102216.2650183 2014 13468302.9834611 2015 15995497.0088246 2016 15082852.3281559 2017 15715178.4940854 2018 15671498.4907774 2019 17127146.1912249 2020 15729005.4414938 2021 15431109.3039141