Year	TDS, current US$
1970	567000
1971	571000
1972	720000
1973	661000
1974	693000
1975	818306.4
1976	1033183.8
1977	1511126.9
1978	2502453.7
1979	3211368.3
1980	4312452.4
1981	4945225.3
1982	8142775.2
1983	10031716.2
1984	11939270
1985	12849256
1986	15743751.2
1987	20607495.7
1988	20851426.6
1989	19020947
1990	33325744.2
1991	16685006.2
1992	12617530.2
1993	12847492.4
1994	15763980
1995	11321809.5
1996	21846662.7
1997	14931132.2
1998	13458874.3
1999	20890921.4
2000	13289603.3
2001	14387976.1
2002	14314028.8
2003	18525018.4
2004	21905446.9
2005	21822437.3
2006	24033399.2
2007	28368738.4
2008	39585414.3
2009	39640014.6
2010	37866416.6
2011	34317205.4
2012	30278272.4
2013	25596654.6
2014	21805509.6
2015	18536883.8
2016	18791852.2
2017	20780337.1
2018	19719398.6
2019	24166239.8
2020	28575894.8
2021	30689103.9
2022	33191806