Year	constant 2015 US$
1995	17576.64264327766
1996	18939.329274742664
1997	19620.617919867374
1998	20496.392363384373
1999	21790.358796664794
2000	22711.28547526715
2001	22399.79186246896
2002	23015.71045163201
2003	22138.14389279626
2004	26434.043530831634
2005	24454.52190865584
2006	24666.697939897287
2007	26629.137969843006
2008	30820.89708408146
2009	31178.00630308283
2010	30936.70412847953
2011	32903.35172079884
2012	32308.8100959944
2013	33931.25727407146
2014	36264.18865454569
2015	37090.82313354804
2016	36441.16106900672
2017	37827.317607071804
2018	38467.061940893116
2019	38973.58789831006
2020	39503.270519639744
2021	38181.989160161844
2022	37588.37396621439