Year	constant 2010 US$
1991	396.639861922287
1992	381.852628242126
1993	369.94554910683
1994	389.244383080852
1995	378.716153945648
1996	390.151108545607
1997	402.27457789972
1998	403.48639573482
1999	413.206604742909
2000	428.14297498792
2001	440.856250012357
2002	445.575567118587
2003	454.439257483564
2004	470.599065913111
2005	480.973268503084
2006	481.985671004191
2007	479.713160446349
2008	504.03349732004
2009	514.097862071945
2010	518.677912856684
2011	537.986955479276
2012	562.235791658708
2013	566.583470858973
2014	590.687570116545
2015	592.045531251446
2016	578.688201109651
2017	597.166944200886
2018	599.225169408319