Year	Number
1960	128063
1961	130602
1962	133174
1963	135752
1964	138429
1965	140833
1966	142774
1967	144603
1968	146275
1969	147414
1970	147931
1971	147724
1972	146592
1973	144739
1974	142375
1975	139448
1976	136787
1977	134355
1978	130545
1979	125145
1980	118617
1981	109617
1982	97715
1983	84768
1984	72596
1985	62444
1986	54329
1987	48522
1988	44719
1989	42290
1990	40577
1991	39562
1992	39225
1993	38646
1994	37502
1995	35309
1996	32436
1997	29862
1998	27678
1999	26096
2000	25058
2001	24152
2002	23368
2003	22933
2004	22792
2005	22720
2006	22704
2007	22831
2008	23088
2009	23344
2010	23554
2011	23777
2012	24180
2013	24465
2014	24654
2015	24896
2016	24923
2017	24698
2018	24192
2019	23465
2020	22578
2021	21570
2022	20489