Year	Number
1975	560023
1976	539202
1977	490877
1978	458615
1979	441596
1980	422415
1981	408349
1982	433029
1983	418762
1984	391295
1985	424014
1986	462221
1987	507273
1988	548412
1989	601260
1990	604447
1991	736351
1992	735113
1993	693918
1994	643594
1995	583100
1996	528961
1997	498442
1998	552521
1999	315438
2000	278212
2001	248838
2002	223425
2003	196576
2004	204996
2005	200130
2006	189607
2007	187248
2008	198498
2009	232822
2010	160880
2011	130547
2012	138376
2013	109892
2014	122434
2016	118433
2017	93279
2018	64709
2019	42275