Year Number 1961 841.1489361702128 1962 902.0114895363153 1963 957.1656391286477 1964 1007.0002466902392 1965 1060.1267176828767 1966 1108.5619086795557 1967 1158.2745456054445 1968 1194.5287566489362 1969 1237.912673943838 1970 1259.1741967871487 1971 1289.4141245298788 1972 1295.5073308897036 1973 1302.2093411175981 1974 1303.4034941763728 1975 1310.1752346150652 1976 1306.772565566311 1977 1317.294341810952 1978 1321.2932318384908 1979 1333.9072737828649 1980 1341.2319201995012 1981 1345.2882372542485 1982 1354.0901878914403 1983 1366.9357399515334 1984 1370.9638554216867 1985 1372.9405369239776 1986 1375.0284280936455 1987 1368.3281707827543 1988 1353.3495145631068 1989 1334.7250815967864 1990 1309.4144181772617 1991 1297.6901116013496 1992 1152.7862562134821 1993 1113.3949982870845 1994 1068.5302837780603 1995 1027.2074355724546 1996 1005.4921841994085 1997 943.2243069641651 1998 902.6104890984091 1999 871.912535949924 2000 838.2645713317519