Year	constant 2015 US$
1997	1248965743.564326
1998	1342208765.6771834
1999	1463670070.7978792
2000	1495568999.4154358
2001	1578996966.569045
2002	1583904494.048669
2003	1645248587.54397
2004	1720088381.6082373
2005	1761802365.1850417
2006	1829280868.029873
2007	1959330346.2399106
2008	1949515291.2806625
2009	1748306664.6160758
2010	1652609878.7634063
2011	1515199109.3339322
2012	1408460386.6521087
2013	1397418449.8229544
2014	1387603394.863706
2015	1419400403.8278778
2016	1452676910.1297214
2017	1456428672.9285338
2018	1478186338.327744
2019	1508721013.9342492
2020	1408422586.4216962
2021	1527618401.7817545