Year	constant 2015 US$
1991	495.64900798185164
1992	487.926136276942
1993	487.6875430467546
1994	478.2687907870164
1995	487.93286768313453
1996	494.6770434214856
1997	494.8283620643201
1998	491.3654452193543
1999	498.6427577688988
2000	505.1612710023089
2001	520.3786684969015
2002	538.9031338084259
2003	549.8380009508448
2004	571.9789922023464
2005	601.1553628494968
2006	622.6378967931279
2007	636.7844705737755
2008	670.3234990412377
2009	689.8703046259823
2010	707.6654465605252
2011	718.6936883055447
2012	729.0293285310813
2013	736.0866751081945
2014	768.755459373289
2015	791.8970922398345
2016	810.3700778418571
2017	838.1159938949475
2018	847.7740720555668
2019	860.1610821569506
2020	871.8546612989369
2021	873.9812580046564
2022	870.3228398419154