Year	constant 2015 US$
1990	9297.697206351839
1991	8596.958176191943
1992	6901.8586952300575
1993	6675.3086542982355
1994	6707.596636704535
1995	7137.53077576403
1996	7601.669018673652
1997	8692.296437614488
1998	9157.064847068528
1999	9091.333194287745
2000	9960.139038774518
2001	10625.579268675221
2002	11417.167968772654
2003	12362.248284302395
2004	13282.545519845025
2005	14631.387325713673
2006	16155.20743003925
2007	17459.098314427825
2008	16607.56806439847
2009	14205.394882976556
2010	14585.838660342904
2011	15692.788829336028
2012	16257.472204351581
2013	16553.383261103
2014	17096.644577158222
2015	17402.037612807875
2016	17945.944964174912
2017	18962.41030064482
2018	19611.61099362805
2019	20327.01586607212
2020	20091.045757335618
2021	21524.68362661964
2022	21140.997219942514
2023	20245.20339732708