Year US Dollars adjusted for inflation) 1991 2799.182 1992 2916.953 1993 2890.373 1994 2895.055 1995 3045.698 1996 3077.316 1997 2996.71 1998 2984.05 1999 2991.972 2000 3042.502 2001 3044.85 2002 3052.077 2003 3087.251 2004 3153.636 2005 3244.305 2006 3226.976 2007 3278.816 2008 3255.573 2009 3242.958 2010 3181.611 2011 3195.256 2012 3237.97 2013 3309.091 2014 3348.715 2015 3422.135 2016 3460.495 2017 3574.458 2018 3697.794 2019 3829.488 2020 3969.014 2021 4116.168 2022 4270.386