Year	annual %
1961	1.070456643767928
1962	2.2520358079092135
1963	1.444161679530016
1964	0.41611341322424944
1965	0.6223743543590169
1966	-1.1231192892873623
1967	0.5081598182503063
1968	0.09408006556942715
1969	-0.42684877677016675
1970	0.39062710799586026
1971	-0.40240672988362164
1972	-1.7874747134921622
1973	-0.8905779529550245
1974	-0.5728881295603137
1975	-1.8560052849089843
1976	-2.5212520735147694
1977	-2.3352229054991556
1978	-1.985454965295121
1979	1.6542932420371996
1980	-1.1631440738705767
1981	-1.43018472475922
1982	-2.1213190263095543
1983	-2.163369690167764
1984	-2.717759989999739
1985	-2.627619134989968
1986	-19.526809582649047
1987	-59.52556020962759
1988	-61.04967722954312
1989	-61.367936050201344
1990	-62.58004276945325
1991	-104.78072635753082
1992	-207.10939897294662