Year	Number
1971	138479
1976	138630
1977	136243
1978	139103
1979	150890
1980	152310
1981	163478
1982	168637
1983	186315
1984	198725
1985	195406
1987	220334
1988	219969
1989	217993
1990	212736
1991	211283
1992	212395
1993	283368
1994	283316
1995	248811
1996	251028
1997	257339
1998	243095
1999	292067
2000	282478
2001	293265
2002	275887
2003	258379
2004	192615
2005	201335
2006	210024
2007	222570
2008	232871
2009	237223
2010	234966
2011	226659
2012	182145
2013	245912
2014	222564
2015	198084
2016	185218
2017	186467