Year US Dollars adjusted for inflation) 1991 990.018 1992 894.291 1993 876.286 1994 879.172 1995 868.417 1996 861.884 1997 847.795 1998 897.469 1999 853.776 2000 806.222 2001 831.876 2002 832.347 2003 850.994 2004 826.059 2005 838.095 2006 856.478 2007 849.445 2008 894.95 2009 852.556 2010 886.66 2011 870.897 2012 939.552 2013 952.594 2014 982.179 2015 979.265 2016 991.082 2017 1004.515 2018 1026.314 2019 1050.929 2020 1085.557 2021 1115.224 2022 1151.716