1962    53.292
1963    53.625
1964    53.991
1965    54.350
1966    54.643
1967    54.959
1968    55.214
1969    55.461
1970    55.632
1971    55.928
1972    56.097
1973    56.223
1974    56.236
1975    56.226
1976    56.216
1977    56.190
1978    56.178
1979    56.240
1980    56.330
1981    56.352
1982    56.318
1983    56.377
1984    56.506
1985    56.685
1986    56.852
1987    57.009
1988    57.158
1989    57.358
1990    57.561
1991    57.808
1992    58.006
1993    58.191
1994    58.395