Year	Number
1970	20214900
1971	26418500
1972	31276100
1973	35824400
1974	34464300
1975	36503600
1976	44661100
1977	58365800
1978	67799000
1979	65482500
1980	59049600
1981	55080800
1982	48596000
1983	45285000
1984	43977300
1985	45541500
1986	47059600
1987	48899300
1988	49481100
1989	47615200
1990	45541200
1991	45859600
1992	46835000
1993	47708000
1994	47391100
1995	49816643
1996	53709790
1997	57396761
1999	64683886
2000	69160881
2003	84326729
2006	85888817
2007	84602299
2008	82541838
2009	80614978
2010	78798728
2011	77152865
2012	75307817
2013	73184068
2014	69457941
2015	68571877
2016	67386565
2017	67415104
2018	68394471