Year	current US$
1960	10.023439067154001
1961	8.893615699325379
1962	8.909204519961204
1963	9.61787269931861
1964	6.135257699987939
1965	7.681327629540889
1966	7.835078343912982
1967	8.59879003409517
1968	7.770531752455534
1969	10.724611179507837
1970	8.519322827163645
1971	9.86871425676018
1972	10.906597958424411
1973	8.26903110912133
1974	7.265019623858904
1975	7.014594958792343
1976	6.0292581479479095
1977	6.513823135491699
1978	4.441807594997482
1979	3.566344086778588
1980	3.638412164426712
1981	8.532084257199655
1982	0.8589659874706127
1983	0.19142878277840492
1984	-0.9127367526736702
1985	-0.21614603313749703
1986	-0.42631481228352025
1987	0.25611645868805666
1988	0.2207881134949717
1989	1.2172242435492955
1990	1.2195211844176845
1991	1.2569375975257338
1992	-0.07086044155914212
1993	-0.7944404602829014
1994	-2.558827570843972
1995	1.2640545400947123
1996	-3.2707531524819253
1997	-3.4741579197199437
1998	-1.0882221742239806
1999	-1.1819803988628597
