Year	Number
1960	8189
1961	8189
1962	8189
1963	8189
1964	8189
1965	9790
1966	9790
1967	9790
1968	9790
1969	9790
1970	18299
1971	18299
1972	18299
1973	18299
1974	18299
1975	29977
1976	31957
1977	35271
1978	40153
1979	45852
1980	49508
1981	54741
1982	60884
1983	67632
1984	72828
1985	77134
1986	80714
1987	85636
1988	94380
1989	103323
1990	112452
1991	120237
1992	128051
1993	142277
1994	151143
1995	166895
1996	176320
1997	217988
1998	260736
1999	268080
2000	282909
2001	288818
2002	273218
2003	280790
2004	303425
2005	320294
2006	331061
2007	394416
2008	370381
2009	387318
2010	362934
2011	368846
2012	410988
2013	437643
2014	371902
2015	344853
2016	350455
2017	294280
2018	302754
2019	272656
2020	249231
2021	203971
2022	168517