Year US Dollars adjusted for inflation) 1984 376.61933 1985 382.01128 1986 383.80122 1987 388.70668 1988 399.70424 1989 419.85992 1990 431.88172 1991 448.02715 1992 476.77575 1993 505.11003 1994 539.60812 1995 581.07608 1996 625.58427 1997 667.14286 1998 696.61002 1999 721.23567 2000 761.61017 2001 800.25993 2002 842.36552 2003 891.87118 2004 950.12991 2005 1012.37071 2006 1073.0128 2007 1138.87368 2008 1191.99875 2009 1244.03715 2010 1310.37027 2011 1377.13398 2012 1433.12914 2013 1493.56251 2014 1565.0205 2015 1651.23468 2016 1735.29095 2017 1834.65159