Year Number 1961 1353.1936379702095 1962 1400.5531807895397 1963 1490.0747615364785 1964 1560.7087024491923 1965 1645.724119671697 1966 1741.2398921832885 1967 1843.6984039625756 1968 1929.3855991103696 1969 1997.4722222222222 1970 2082.045518404046 1971 2137.8537405435695 1972 2162.534435261708 1973 2224.366041896362 1974 2268.7465790914066 1975 2306.2618595825425 1976 2362.6522327469556 1977 2419.572857529062 1978 2443.37863042899 1979 2491.377023083046 1980 2521.962739438468 1981 2545.501820072803 1982 2563.641038827462 1983 2572.877059569075 1984 2567.0974155069584 1985 2592.4444444444443 1986 2645.384805741153 1987 2728.8688236769503 1988 2752.362008950771 1989 2755.751346059716 1990 2833.440673767649 1991 2797.5460122699383 1992 2797.3405565131743 1993 2761.6491827274945 1994 2690.8396946564885 1995 2662.2453813358597 1996 2661.1546685673557 1997 2681.107099879663 1998 2680.8613597870794 1999 2683.8772528007794 2000 2681.0176125244616 2001 2662.4328285295555 2002 2654.9106049473426 2003 2649.9877119685425 2004 2642.0664206642064 2005 2634.170359428853 2006 2619.164619164619 2007 2611.903590752582