Year	Number
1960	35070
1961	34155
1962	33388
1963	32792
1964	32290
1965	31872
1966	31466
1967	31004
1968	30472
1969	29965
1970	29458
1971	28818
1972	28122
1973	27458
1974	26792
1975	26156
1976	25554
1977	24951
1978	24270
1979	23502
1980	22709
1981	24299
1982	27605
1983	20287
1984	19690
1985	19163
1986	18688
1987	18195
1988	17627
1989	16972
1990	16326
1991	15638
1992	15013
1993	14543
1994	14129
1995	13645
1996	13127
1997	12607
1998	12133
1999	11735
2000	11390
2001	11213
2002	11115
2003	11001
2004	10954
2005	10972
2006	11024
2007	11404
2008	12126
2009	12345
2010	12184
2011	15169
2012	27946
2013	29843
2014	25513
2015	21615
2016	14903
2017	14889
2018	15170
2019	9808
2020	8703
2021	8806
2022	9136