Year US Dollars adjusted for inflation) 1991 2813.847 1992 2429.591 1993 2316.907 1994 2138.751 1995 2066.994 1996 2086.919 1997 2138.025 1998 2168.808 1999 2200.196 2000 2221.293 2001 2248.8 2002 2274.249 2003 2305.073 2004 2415.192 2005 2511.001 2006 2617.81 2007 2797.852 2008 2964.823 2009 3116.408 2010 3289.963 2011 3477.992 2012 3670.311 2013 3867.475 2014 4074.904 2015 4311.706 2016 4559.509 2017 4752.995 2018 4959.854 2019 5206.952 2020 5463.813 2021 5749.985 2022 6058.435