Year	Number
1960	21465
1961	21534
1962	21503
1963	21446
1964	21460
1965	21585
1966	21824
1967	22189
1968	22608
1969	22963
1970	23221
1971	23387
1972	23491
1973	23600
1974	23755
1975	23967
1976	24238
1977	24572
1978	24998
1979	25571
1980	26311
1981	27184
1982	28170
1983	29291
1984	30608
1985	32126
1986	33843
1987	35771
1988	37803
1989	39792
1990	41671
1991	43415
1992	44976
1993	46385
1994	47767
1995	49196
1996	50644
1997	52108
1998	53550
1999	54899
2000	56120
2001	57257
2002	58338
2003	59359
2004	60307
2005	61190
2006	62027
2007	62877
2008	63807
2009	64850
2010	66027
2011	67272
2012	68489
2013	69730
2014	71484
2015	73855
2016	76575
2017	79678
2018	83063
2019	86674
2020	90356
2021	92988
2022	96112
2023	100783