Year	current US$
1988	34000000
1989	44000000
1990	56000000
1991	56000000
1992	62000000
1993	61000000
1994	70000000
1995	75000000
1996	73000000
1997	61000000
1998	67000000
1999	69000000
2000	55000000
2001	56000000
2002	68000000
2003	75000000
2004	84000000
2005	94000000
2006	91000000
2007	100000000
2008	100000000
2009	105000000
2010	150000000
2011	130000000
2012	140000000
2013	147000000
2014	136000000
2015	108000000
2016	97000000
2017	90000000
2018	75000000
2019	68000000
2020	74000000
2021	81000000
2022	94000000
2023	103000000