Year	Number
1960	3316
1961	3316
1962	3316
1963	3316
1964	3316
1965	13000
1966	13000
1967	13000
1968	13000
1969	13000
1970	38000
1971	38000
1972	38000
1973	38000
1974	38000
1975	89000
1976	103000
1977	114000
1978	126000
1979	139000
1980	157000
1981	170213
1982	191605
1983	203969
1984	210226
1985	221882
1986	235447
1987	254826
1988	281771
1989	310837
1990	331406
1991	321909
1992	345583
1993	357996
1994	372719
1995	382287
1996	391841
1997	411629
1998	427288
1999	455643
2000	467067
2001	472414
2002	481891
2003	486904
2004	496973
2005	504806
2006	516982
2007	538219
2008	519966
2009	528497
2010	519418
2011	514696
2012	510000
2013	508000
2014	494000
2015	480000
2016	533234
2017	542082
2018	515542
2019	583463
2020	583463
2022	572511