Year US Dollars adjusted for inflation) 1991 935.237 1992 991.32 1993 1045.415 1994 1110.731 1995 1187.832 1996 1269.624 1997 1353.3 1998 1386.932 1999 1417.663 2000 1478.535 2001 1538.348 2002 1589.166 2003 1667.032 2004 1755.14 2005 1850.255 2006 1945.035 2007 2045.879 2008 2120.667 2009 2198.844 2010 2292.572 2011 2373.552 2012 2444.839 2013 2535.88 2014 2640.234 2015 2794.417 2016 2946.554 2017 3108.479 2018 3284.962 2019 3468.187 2020 3655.323 2021 3852.494 2022 4054.05