Year	Number
1960	76681
1961	82251
1962	88270
1963	94565
1964	100876
1965	106504
1966	109044
1967	111320
1968	113263
1969	114563
1970	115111
1971	116410
1972	117038
1973	117414
1974	117685
1975	116351
1976	108172
1977	100476
1978	93035
1979	85753
1980	77965
1981	68112
1982	59274
1983	51491
1984	44425
1985	39612
1986	40995
1987	42363
1988	43733
1989	45084
1990	33934
1991	26951
1992	32380
1993	32808
1994	32346
1995	31515
1996	28531
1997	25946
1998	23563
1999	21365
2000	19349
2001	1832
2002	0
2003	0
2004	0
2005	0
2006	0
2007	0
2008	0
2009	0
2010	0
2011	0
2012	0
2013	0
2014	0
2015	0
2016	0
2017	0
2018	0
2019	0
2020	0
2021	0
2022	0
2023	0