Year	Number
1960	65783
1961	59646
1962	54414
1963	50152
1964	46672
1965	44099
1966	37668
1967	35706
1968	36709
1969	34410
1970	33012
1971	32265
1972	31562
1973	30702
1974	29205
1975	26810
1976	24310
1977	22056
1978	20033
1979	18156
1980	16447
1981	14869
1982	13540
1983	12552
1984	11694
1985	10874
1986	10057
1987	9439
1988	8994
1989	8487
1990	8031
1991	7787
1992	7608
1993	7362
1994	7200
1995	6957
1996	6644
1997	6352
1998	6030
1999	5700
2000	5435
2001	5183
2002	4905
2003	4656
2004	4434
2005	4228
2006	4074
2007	3961
2008	3831
2009	3684
2010	3533
2011	3503
2012	3239
2013	3114
2014	2977
2015	2850
2016	2726
2017	2543
2018	2359
2019	2197
2020	2060
2021	1961
2022	1879