Year	Number
1960	48250
1961	48027
1962	49297
1963	50686
1964	52188
1965	53827
1966	55783
1967	58205
1968	61097
1969	64477
1970	68234
1971	71249
1972	73247
1973	74986
1974	76514
1975	77855
1976	79000
1977	79922
1978	80592
1979	80979
1980	81077
1981	82446
1982	85703
1983	89578
1984	93770
1985	98331
1986	103181
1987	108134
1988	113096
1989	117910
1990	122476
1991	126484
1992	129349
1993	131758
1994	134590
1995	137732
1996	141151
1997	144942
1998	149028
1999	153297
2000	157840
2001	163091
2002	169785
2003	177585
2004	185775
2005	194081
2006	202285
2007	210461
2008	218477
2009	226077
2010	233305
2011	239677
2012	244388
2013	248171
2014	252018
2015	255831
2016	259484
2017	262946
2018	266065
2019	268866
2020	271490
2021	272678
2022	272984
2023	273728