Year	Number
1960	1302750
1961	1302750
1962	1302750
1963	1302750
1964	1302750
1965	1775000
1966	1775000
1967	1775000
1968	1775000
1969	1775000
1970	2845000
1971	2845000
1972	2845000
1973	2845000
1974	2845000
1975	4698000
1976	5118000
1977	5679000
1978	6185000
1979	6698000
1980	7228800
1981	7654200
1982	8017690
1983	8453700
1984	8881727
1985	9340458
1986	9785300
1987	10236408
1988	10971635
1989	11797159
1990	12602600
1991	13264360
1992	13792156
1993	14253470
1994	14685406
1995	15095377
1996	15412785
1997	15854448
1998	16288605
1999	16480426
2000	17104000
2001	17531000
2002	17640745
2003	17759164
2004	17934477
2005	19460832
2006	19865037
2007	20192505
2008	20576070
2009	20244312
2010	20181424
2011	19889038
2012	19574626
2013	19384245
2014	19236519
2015	19373709
2016	19487737
2017	19587220
2018	19762671
2019	19639778
2020	19455658
2021	19060635
2022	18687040