Year	constant 2015 US$
1997	339565101.13832843
1998	334166016.0311438
1999	349504236.24756294
2000	327729591.77716845
2001	307311540.7417563
2002	288165565.15487987
2003	270212413.06063306
2004	253377769.54698384
2005	247861937.66982898
2006	263725101.68069804
2007	271636854.731119
2008	252622274.96898296
2009	254643253.1797816
2010	251254800.29137337
2011	248742252.13656655
2012	242772438.16399717
2013	267049681.96313632
2014	288413656.48566604
2015	269320537.2843919
2016	272575183.56276476