Year	Number
1970	117612288
1971	121142656
1972	120062880
1973	112892960
1974	111992440
1975	109157040
1976	108674960
1977	111133616
1978	118910952
1979	118935184
1980	116222152
1981	112476616
1982	111404560
1983	110310736
1984	109108568
1985	105848088
1986	102182728
1987	101628120
1988	99040112
1989	96593792
1990	99707440
1991	99179720
1992	101425848
1993	102395240
1994	103844712
1995	108047024
1996	111466912
1997	112481840
1998	109044440
1999	102493744
2000	96849216
2001	93069632
2002	89581680
2003	79688992
2004	74564776
2005	69343848
2006	68274928
2007	60156156
2008	58426204
2009	59230120
2010	60200000
2011	59700000
2012	57800000
2013	56700000
2014	56100000
2015	57700000
2016	57200000
2017	57600000
2018	57800000