Year	Number
1975	646858
1976	612799
1977	550814
1978	502398
1979	469234
1980	431677
1981	395119
1982	400136
1983	371905
1984	335856
1985	367197
1986	407198
1987	454226
1988	500230
1989	556773
1990	562459
1991	693402
1992	705606
1993	675299
1994	634103
1995	583468
1996	540845
1997	511516
1998	555400
1999	476236
2000	395537
2001	335353
2002	260264
2003	239738
2004	242278
2005	217175
2006	187923
2007	164093
2008	155625
2009	172784
2010	125794
2011	115570
2012	131554
2013	108415
2014	119995
2016	100313