Year US Dollars adjusted for inflation) 1991 1706.045 1992 1683.221 1993 1677.957 1994 1691.498 1995 1725.94 1996 1894.432 1997 1985.214 1998 1398.415 1999 1392.565 2000 1440.165 2001 1435.299 2002 1387.415 2003 1361.884 2004 1366.16 2005 1386.414 2006 1380.868 2007 1387.883 2008 1393.482 2009 1399.492 2010 1420.195 2011 1510.901 2012 1437.772 2013 1408.5 2014 1401.429 2015 1427.811 2016 1465.899 2017 1485.048 2018 1505.569 2019 1529.302 2020 1555.849 2021 1582.475 2022 1610.724