Year	Number
1960	326550
1961	325250
1962	323900
1963	322550
1964	321250
1965	318800
1966	315200
1967	311550
1968	307900
1969	304300
1970	302650
1971	302700
1972	302450
1973	302200
1974	301996
1975	304222
1976	305774
1977	306970
1978	310182
1979	313342
1980	316645
1981	318982
1982	325898
1983	330524
1984	330593
1985	336452
1986	342121
1987	344485
1988	347325
1989	350722
1990	354170
1991	363845
1992	367618
1993	371308
1994	374797
1995	377419
1996	379905
1997	382791
1998	385287
1999	387578
2000	390087
2001	393028
2002	395969
2003	398582
2004	401268
2005	403834
2006	405308
2007	406724
2008	409379
2009	412477
2010	414508
2011	416268
2012	420028
2013	425967
2014	434558
2015	445053
2016	455356
2017	467999
2018	484630
2019	504062
2020	515332
2021	518536
2022	531113
2023	553214