Year	Number
1961	27000
1962	27300
1963	27500
1964	28000
1965	28300
1966	30000
1967	39500
1968	39800
1969	40000
1970	40200
1971	40500
1972	40700
1973	41000
1974	41300
1975	41500
1976	41800
1977	42000
1978	42147
1979	45847
1980	47000
1981	48000
1982	49200
1983	50279
1984	61319
1985	75310
1986	82647
1987	89271
1988	91700
1989	79809
1990	91426
1991	98157
1992	91586
1993	96540
1994	90567
1995	91204
1996	92023
1997	92426
1998	92800
1999	94259
2000	95717
2001	97176
2002	97700
2003	97800
2004	97809
2005	100128
2006	102363
2007	103558
2008	104529