Year current US$ 1976 1024.72302246094 1977 1332.72424316406 1978 1734.13745117188 1979 2287.0849609375 1980 3762.48657226563 1981 3545.2119140625 1982 3620.51586914063 1983 3547.87377929688 1984 3690.63061523438 1985 3878.41479492188 1986 4807.759765625 1987 5708.23291015625 1988 6525.63232421875 1989 6882.02099609375 1990 8259.68359375 1991 8310.265625 1992 9681.50390625 1993 9017.1201171875 1994 9940.1640625 1995 12442.8740234375 1996 12306.1826171875 1997 11472.2919921875 1998 13496.974609375 1999 12438.0390625 2000 11346.9306640625 2001 11974.1357421875 2002 13312.5478515625 2003 17016.919921875 2004 19631.4921875 2005 20741.3828125 2006 22178.787109375 2007 25734.27734375 2008 30762.45703125 2009 28200.1171875 2010 26890.353515625 2011 29378.478515625 2012 25145.888671875 2013 23695.255859375 2014 22731.18359375 2015 20165.8515625 2016 20629.857421875 2017 22676.0390625 2018 24887.5703125 2019 24414.591796875 2020 22488.416015625 2021 24687.482421875