Year	Number
1970	348757.8
1971	353595.3
1972	373855.9
1973	387504.2
1974	395090.3
1975	448954.9
1976	479091.5
1977	493992.4
1978	506330.4
1979	514646.2
1980	527545.1
1981	507341.8
1982	507668.4
1983	510999.8
1984	509083.3
1985	521515.2
1986	530934.6
1987	535653.8
1988	542477.6
1989	528939.4
1990	526828.1
1991	529450
1992	527034.6
1993	524130.5
1994	542922.1
1995	565496.1
1996	592178.8
1997	607717
1998	537255.6
1999	547829.8
2000	552348.5
2001	555364.6
2002	553178.8
2003	549819.9
2004	563622.9
2005	567526.7
2006	575866.4
2007	579585.3
2008	588357.4
2009	587974.3
2010	585296.1
2011	587992.5
2012	571061.1
2013	552634.1
2014	546983.3
2015	531381.1
2016	534544.1
2017	518369.7
2018	513048.1