Year	constant 2015 US$
1991	4801.515359002507
1992	4801.369528379411
1993	4833.949236904506
1994	4773.531077668216
1995	4733.091232065388
1996	4675.765876124625
1997	4665.2160813744
1998	4676.273334546367
1999	4687.726384372979
2000	4638.92303997895
2001	4757.96068158698
2002	5073.053918762181
2003	4965.618652167041
2004	5632.227519342764
2005	5954.075126206248
2006	6374.733007997864
2007	6852.7076101560615
2008	7412.688331403398
2009	7953.4058453457
2010	8583.200910600242
2011	8608.639377663503
2012	8701.554585833645
2013	9159.048921156276
2014	9603.201944572578
2015	9891.125502002407
2016	9707.477614004658
2017	9530.452185092163
2018	9580.427111937972
2019	9635.203645679929
2020	9409.152615863213
2021	9582.771853384775
2022	9639.190367358731