Year current US$ 1980 263.0198405637486 1981 234.68966132428798 1982 224.775937144467 1983 198.0287269803805 1984 175.16198725173373 1985 180.70687490384546 1986 230.46558806793928 1987 259.4419617795835 1988 278.54036773771196 1989 271.09361094726904 1990 313.13367979088 1991 308.73081299118405 1992 322.15377303041964 1993 298.98850446242943 1994 170.69910021445796 1995 210.65654751153525 1996 225.04013662250625 1997 206.30170726487248 1998 228.81293104131817 1999 269.1878944748566 2000 233.75457501545836 2001 243.01375538351596 2002 265.29239578969776 2003 336.3490835808683 2004 373.4293285978743 2005 406.49021413423793 2006 419.95028927404417 2007 474.6291235860205 2008 566.8196937528371 2009 538.9361170096419 2010 538.3932838289436 2011 602.8918517550962 2012 631.1646560964026 2013 658.7496037490968 2014 656.082792655148 2015 544.8716655694815 2016 576.2285200420347 2017 615.0970087113045 2018 678.9177715695594 2019 653.2212124632064 2020 682.5431243859787 2021 666.8583775437484