Year	Number
1971	52232
1972	59454
1973	65442
1974	72059
1975	77389
1976	83811
1977	88230
1978	92103
1979	101159
1980	104796
1981	109546
1982	116559
1983	121704
1984	128967
1985	134509
1986	140942
1987	146522
1988	152595
1989	158569
1990	169772
1991	180724
1992	188860
1993	192662
1994	192703
1995	188858
1996	190667
1997	192851
1998	192459
1999	188751
2000	188327
2001	189273
2002	200805
2003	206163
2004	207878
2005	209676
2006	214228
2007	216947
2008	219288
2009	221689
2010	224503
2011	239292
2012	237375
2013	238301
2014	239996
2015	235768
2016	233461
2017	231582
2018	230340
2019	228907
2020	227135
2021	227317
2022	228998