Year	Number
1961	10829
1962	11971
1963	13242
1964	14257
1965	15354
1966	17234
1967	17418
1968	18878
1969	19356
1970	19674
1971	22461
1972	23976
1973	25088
1974	25545
1975	25880
1976	26618
1977	27629
1978	28615
1979	29703
1980	30948
1981	32031
1982	33421
1983	34601
1984	35566
1985	33958
1986	34471
1987	34995
1988	36062
1989	36520
1990	38657
1991	38001
1992	87765
1993	85338
1994	85305
1995	86129
1996	84715