Year US Dollars adjusted for inflation) 1991 913.304 1992 837.48 1993 919.396 1994 819.347 1995 950.567 1996 1003.067 1997 1016.309 1998 1025.953 1999 1027.323 2000 1013.021 2001 938.488 2002 931.044 2003 959.068 2004 983.069 2005 985.448 2006 997.615 2007 1057.604 2008 1098.787 2009 1148.501 2010 1182.53 2011 1194.767 2012 1170.542 2013 1184.538 2014 1211.597 2015 1204.916 2016 1194.647 2017 1203.555 2018 1219.65 2019 1242.557 2020 1272.166 2021 1300.349 2022 1330.306