Year	Number
1971	64264
1972	63406
1973	64428
1974	65210
1975	65794
1976	66058
1977	66316
1978	66190
1979	65319
1980	61842
1981	61139
1982	59929
1983	60859
1984	60976
1985	62624
1986	35525
1987	36926
1988	39056
1989	40065
1990	40850
1991	41631
1992	42910
1993	46309
1994	4486
1995	4060
1996	4482
1997	5635
2017	1529
2018	1913
2019	1276
2020	1587
2021	1748