Year	Number
1961	367385
1962	395279
1963	423936
1964	452914
1965	478390
1966	501415
1967	521288
1968	544220.52
1969	567364.12
1970	579136.72
1971	600146.0800000001
1972	623099.08
1973	653715.88
1974	667645.04
1975	763890.48
1976	797262.3200000001
1977	824448.32
1978	847643
1979	911919
1980	970682
1981	1072856
1982	1093914
1983	1124889
1984	1156220
1985	1207765.57
1986	1270266.1400000001
1987	1330722.71
1988	1387096
1989	1419575
1990	1456170
1991	1486279
1992	1493944
1993	1500829
1994	1510488
1995	1517546
1996	1510469
1997	1513865
1998	1483858
1999	1477451
2000	1471640