Year	current US$
1995	205000000
1996	142000000
1997	190000000
1998	656000000
1999	559000000
2000	677000000
2001	1122000000
2002	1607000000
2003	1266000000
2004	1305000000
2005	1025000000
2006	1464000000
2007	1950000000
2008	1978000000
2009	2259000000
2010	2631000000
2011	2489000000
2012	2483000000
2013	3306000000
2014	4197000000
2015	4771000000
2016	4634000000
2017	4531000000
2018	5252000000