Year	Number
1960	10330
1961	10467
1962	10597
1963	10698
1964	10829
1965	10928
1966	10991
1967	11086
1968	11187
1969	11257
1970	11378
1971	11577
1972	11782
1973	11990
1974	12207
1975	12487
1976	12679
1977	12795
1978	12927
1979	13000
1980	13034
1981	13065
1982	13288
1983	13472
1984	13585
1985	13961
1986	14380
1987	14737
1988	15144
1989	15607
1990	16088
1991	16803
1992	17195
1993	17588
1994	18053
1995	18533
1996	18934
1997	19331
1998	19768
1999	20248
2000	20796
2001	21432
2002	22107
2003	22771
2004	23417
2005	23972
2006	24331
2007	24793
2008	25972
2009	27577
2010	29129
2011	30647
2012	32196
2013	33770
2014	35407
2015	37039
2016	38432
2017	39835
2018	41506
2019	43456
2020	44652
2021	45140
2022	47002
2023	50191