Year	Number
1970	5376841
1971	5541948
1972	5172912
1973	5122432
1974	5137389
1975	4838144
1976	4622354
1977	4496301
1978	4413350
1979	4666124
1980	4328380
1981	4492739
1982	4345654
1983	4313974
1984	4217607
1985	4223137
1986	4151927
1987	4082060
1988	4004986
1989	4108872
1990	3703140
1991	3633007
1992	4335092
1993	4328991
1994	3942620
1995	4343103
1996	3830889
1997	3899635
1998	3906084
1999	3703147
2000	3392050
2001	2901988
2002	2426063
2003	2195036
2004	2042456
2005	2044475
2006	2040332
2007	1835940
2008	1560600
2009	1414738
2010	1221257
2011	1179680
2012	1067477
2013	1255130