Year	constant 2015 US$
1991	15532.109884221922
1992	15742.827362319767
1993	15715.308336849459
1994	15992.59757702155
1995	15981.407473144103
1996	16372.759266032972
1997	16312.883229479443
1998	16025.668423205363
1999	15860.790333539602
2000	15578.702094457936
2001	15680.692932537586
2002	16275.39678692688
2003	16596.019617164817
2004	16828.970963597854
2005	17524.808028747557
2006	18419.13260322912
2007	19882.062689200797
2008	20052.794818214526
2009	19655.15676798468
2010	20658.258839060083
2011	21553.22847777163
2012	21306.6635689749
2013	20934.403478914664
2014	20968.8119287459
2015	19587.078934634676
2016	19518.57539938904
2017	19069.935205223508
2018	18775.29033501518
2019	18416.820117390984
2020	20084.4432568121
2021	21009.786799174693
2022	20223.4193468602