Year	Number of
1969	1756000
1970	1762000
1971	1768000
1972	1783000
1973	1802000
1974	1813000
1975	1815000
1976	1804000
1977	1787000
1978	1768000
1979	1755000
1980	1744000
1981	1743000
1982	1748000
1983	1752000
1984	1748000
1985	1733000
1986	1704000
1987	1663000
1988	1619000
1989	1575000
1990	1537000
1991	1502000
1992	1470000
1993	1445000
1994	1419000
1995	1397000
1996	1374000
1997	1345000
1998	1319000
1999	1289000
2000	1254000
2001	1216000
2002	1176000
2003	1134000
2004	1092000
2005	1054000
2006	1017000
2007	981800
2008	946300
2009	909600
2010	871300
2011	831100
2012	792600
2013	752700
2014	721700
2015	695900