Year TDS, current US$ 1975 36000 1976 60000 1977 60000 1978 66000 1979 162000 1980 276000 1981 508000 1982 637000 1983 679000 1984 1284568.4 1985 1752669.2 1986 2074853.6 1987 2593108.7 1988 3143530.6 1989 1824178.4 1990 2107380.6 1991 2575690.3 1992 3077164.2 1993 5064346.1 1994 4301911.4 1995 4185017.7 1996 3858343.2 1997 3772446.7 1998 4455148.5 1999 4652986.7 2000 4266857.9 2001 4748443.4 2002 5495714.7 2003 5379160.5 2004 5430937.6 2005 6379855.4 2006 8196539.9 2007 9430726.4 2008 11563279.8 2009 12099053.7 2010 11242627.4 2011 12247784.2 2012 8982520.9 2013 14806227.1 2014 13667550.7 2015 14551586.1 2016 16200054.2 2017 17570501.8 2018 18440870 2019 19135693.2 2020 18089341.5 2021 20332895.4 2022 19946231.8