Year	Number
1960	8130
1961	8130
1962	8130
1963	8130
1964	8130
1965	10231
1966	10231
1967	10231
1968	10231
1969	10231
1970	14977
1971	14977
1972	14977
1973	14977
1974	14977
1975	27056
1976	28766
1977	31777
1978	35021
1979	38283
1980	39770
1981	40704
1982	42007
1983	43987
1984	47509
1985	52064
1986	54460
1987	58919
1988	66058
1989	70640
1990	73011
1991	76369
1992	81306
1993	85005
1994	88315
1995	90270
1996	92760
1997	105095
1998	121769
1999	149611
2000	173591
2001	177802
2002	161590
2003	147006
2004	148360
2005	154360
2006	152000
2007	163269
2008	123809
2009	172922
2010	174511
2011	161063
2012	176367
2013	164999
2014	151274
2015	142819
2016	129597
2017	127094
2018	124238
2019	76288
2020	72469
2021	71834
2022	84696