Year	TDS, current US$
1981	491746.1
1982	477519
1983	1323073
1984	1357400.5
1985	1315773.5
1986	1583856.9
1987	3438772.6
1988	2372095.3
1989	1972346.6
1990	2419401.9
1991	1581714
1992	1502515
1993	1530683.8
1994	1592296
1995	1610234.2
1996	1639025.7
1997	1931240.6
1998	1420496.2
1999	2472708.3
2000	2800888.9
2001	1990554.2
2002	2307609.6
2003	2522978
2004	3992886.1
2005	3360431.7
2006	4569948.4
2007	4658998.2
2008	4719742.1
2009	5680425.5
2010	5881680.5
2011	6113652.9
2012	5583676.4
2013	7211750.1
2014	7877796.3
2015	6968898.3
2016	8735975.5
2017	10041308.4
2018	20155068.7
2019	15882858.1
2020	19320653.7
2021	20022545.4
2022	23788092.4