Year	TDS, current US$
1971	300907.5
1972	325710
1973	357727.5
1974	721605
1978	7437959.1
1979	12620768.8
1980	11640031.4
1981	15215851.8
1982	26203307.6
1983	25925051.1
1984	34528120.3
1985	66469691.5
1986	86414011.8
1987	84677566.8
1988	82511679.4
1989	76669669.4
1990	70050280
1991	57711648
1992	49902915.7
1993	30107618.6
1994	31445229.1
1995	43424854
1996	47936489.8
1997	66028927.4
1998	62543372
1999	35391171.9
2000	23323504.8
2001	24528039.9
2002	24396019.2
2003	33698565.5
2004	36405720.7
2005	35293772.7
2006	1627269.6
2007	1453694.6
2008	451228.2
2009	1013194.1
2010	1310681
2011	3540773.9
2012	5380045.1
2013	5573133.6
2014	17677876.9
2015	33902188.9
2016	35845439.2
2017	33771241.7
2018	34573791.2
2019	24480664.5
2020	6951405.1
2021	4128391.5
2022	17540482.8