Year	Number
1961	62000
1962	70000
1963	78000
1964	86000
1965	94000
1966	102000
1967	110400
1968	118700
1969	127000
1970	135293
1971	140000
1972	144500
1973	149100
1974	153700
1975	156529
1976	160000
1977	164000
1978	168000
1979	172957
1980	178000
1981	178000
1982	180000
1983	183000
1984	183186
1985	183373
1986	183100
1987	182850
1988	182600
1989	182450
1990	182228
1991	182000
1992	180000
1993	178000
1994	176000
1995	172596
1996	167000
1997	161000
1998	155000
1999	149530
2000	148500
2001	147500
2002	146500
2003	145500
2004	144500
2005	144600