Year US Dollars adjusted for inflation) 1980 3223.80899 1981 3370.52919 1982 3439.02826 1983 3548.13215 1984 3660.06888 1985 3758.34003 1986 3917.5148 1987 4148.59381 1988 4597.47543 1989 4498.55198 1990 4162.8157 1991 3849.1863 1992 3607.79367 1993 3582.85612 1994 3660.40198 1995 3781.90349 1996 3828.24642 1997 3809.68651 1998 3967.99605 1999 3750.49383 2000 3955.2758 2001 4186.92042 2002 4532.85387 2003 4804.48436 2004 5152.41401 2005 5561.16384 2006 5988.77095 2007 6476.0542 2008 6914.39843 2009 6709.52731 2010 6843.26695 2011 7019.17405 2012 7062.13498 2013 7162.99779 2014 7299.54877 2015 7612.02236 2016 7967.70817 2017 8311.9309