Year	Number
1960	1561968
1961	1561970
1962	1561970
1963	1561970
1964	1561970
1965	2010000
1966	2010000
1967	2010000
1968	2010000
1969	2010000
1970	2704000
1971	2704000
1972	2704000
1973	2704000
1974	2704000
1975	3539000
1976	3700000
1977	3907000
1978	4165945
1979	4449468
1980	4742662
1981	5069342
1982	5356572
1983	5591667
1984	5850594
1985	6186835
1986	6501468
1987	6816301
1988	7091549
1989	7419982
1990	7786889
1991	8046029
1992	8257000
1993	8540000
1994	8850000
1995	8900000
1996	9170000
1997	9350000
1998	9540000
1999	9760000
2000	10050000
2001	10060000
2002	10400000
2003	10460000
2004	10370000
2005	10120000
2006	9940000
2007	9760000
2008	9370000
2009	10709000
2010	10625000
2011	10573000
2012	10471000
2013	10350000
2014	9190000
2015	8500000
2016	8480000
2017	8460000
2018	8200000
2019	6200000
2020	5455493
2021	6717379
2022	6409275