Year	Number
1971	234689
1972	242119
1973	244711
1974	247593
1975	245210
1976	242809
1977	239798
1978	238536
1979	235434
1980	228138
1981	222890
1982	207011
1983	193141
1984	183968
1985	183206
1986	211148
1987	215568
1988	221600
1989	232917
1990	239572
1991	238867
1992	233528
1993	221713
1994	211235
1995	212401
1996	213337
1997	206570
1998	196351
1999	189851
2000	185752
2001	186135
2002	187756
2003	199347
2004	208614
2005	204359
2006	198135
2007	190721
2008	175546
2009	164412
2010	160123
2011	158312
2012	142924
2013	164584
2014	167635
2015	155132
2016	143399
2017	141163