Year	constant 2015 US$
1998	21917835560.363113
1999	22721193355.131893
2000	26384179912.55801
2001	27990775669.881805
2002	27102230339.49985
2003	26056113110.09358
2004	25148836205.02191
2005	30114549923.46323
2006	24642154440.060673
2007	24493117623.382847
2008	27167970818.707413
2009	28476184802.697292
2010	32536827538.375687
2011	33785222203.039356
2012	35686296627.30579
2013	39430285152.30708
2014	39576893062.19048
2015	39080884265.27959
2016	38329628463.58667
2017	38019952174.89584
2018	39089443709.12008
2019	39846405806.70666
2020	34017076686.75113
2021	38842542601.02838