Year	Number
1961	24
1962	24
1963	24
1964	30
1965	35
1966	40
1967	34
1968	68
1969	100
1970	61
1971	183
1972	212
1973	293
1974	388
1975	564
1976	790
1977	1121
1978	1601
1979	2035
1980	2664
1981	3862
1982	5575
1983	7649
1984	9684
1985	12389
1986	16167
1987	19863
1988	24616
1989	31328
1990	41203
1991	52973
1992	64159
1993	76800
1994	88706
1995	100412
1996	113287
1997	131358
1998	157888
1999	176146
2000	191631
2001	201089
2002	206371
2003	211576
2004	219664
2005	227873
2006	236707
2007	243662
2008	253531