Year US Dollars adjusted for inflation) 1960 20000000 1964 60000000 1965 12000000 1967 128000000 1968 24000000 1975 24000000 1980 18000000 1981 29000000 1982 64000000 1983 115000000 1987 117000000 1988 36000000 1990 80000000 1991 8000000 1993 183000000 1994 272000000 1995 16000000 1999 3000000 2000 18000000 2002 10000000 2003 2000000 2006 5000000 2007 6000000 2008 8000000 2009 10000000 2010 8000000 2011 26000000 2012 26000000 2013 8000000 2014 19000000 2015 22000000 2016 21000000 2017 13000000 2018 25000000 2019 2000000 2021 24000000 2022 67000000