Year	constant 2015 US$
1991	3734.5921627594003
1992	3656.351891509366
1993	3567.7101671049663
1994	3491.333193086897
1995	3435.587243315525
1996	3365.74539494056
1997	3363.3748960373214
1998	3373.05225464406
1999	3385.2956047888765
2000	3428.7093857540294
2001	3330.6279551263283
2002	3225.394401845328
2003	3141.084521533794
2004	3105.4624040511076
2005	3102.9332380326564
2006	3232.069252499432
2007	3468.3431283550112
2008	3707.6478002312547
2009	3937.2651269501685
2010	4093.184027972184
2011	4322.022987491465
2012	4581.957407694363
2013	4812.766840450605
2014	4851.671234570872
2015	4912.310280024924
2016	4998.656033711177
2017	4731.380618072016
2018	4821.629534756923
2019	4958.264107777633
2020	5159.720147636512
2021	5254.727521198774
2022	5399.514223977906