Year	current US$
1960	0.582116542849246
1961	0.5413386326564588
1962	0.6178890326517419
1963	0.5810307024476657
1964	0.5927813253496392
1965	0.7892105929359329
1966	0.9323394399299915
1967	1.0666093626522606
1968	1.0997994124132573
1969	1.1458905976411589
1970	1.2173495461094828
1971	1.3606642875795132
1972	1.4998842646555015
1973	1.6203191354211692
1974	1.9904766835564904
1975	1.6363629195316505
1976	1.3959493836401027
1977	1.3227515123665916
1978	1.8679998133002111
1979	2.173416269606305
1980	2.4164224326768124
1981	2.595999951616056
1982	2.415171768118202
1983	2.423436895292567
1984	2.459328583278111
1985	2.4547058280615035
1986	2.976605907850289
1987	3.481237361084465
1988	4.055863700411203
1989	4.13810177714653
1990	4.5622966869578105
1991	4.329012466883367
1992	5.734609159046934
1993	5.295871370539928
1994	5.411183647107457
1995	5.503509875234225
1996	4.462900717823296
1997	3.7181953335898688
1998	4.547821181199517
1999	5.314185835824358
2000	4.534083548807804
2001	3.8587314592636144
2002	3.776037419674203
2003	3.633556828470299
2004	3.553017252061062
2005	4.880231974586191
2006	3.9429104212566113
2007	3.9386911456519793
2008	4.02590945937298
2009	4.2415709947246265
2010	4.779738655604565
2011	3.7607870766644518
2012	4.413619918303032
2013	5.937373364301564
2014	4.6566172447990395
2015	4.144061996201082
2016	3.727298645075262
2017	4.031392183568429
2018	3.935298348724728
2019	3.354404321985645
2020	5.999279745303863
2021	4.970577517857151
2022	4.477073136536769