Year	Number
1960	14776
1961	14784
1962	14899
1963	15063
1964	15263
1965	15522
1966	15799
1967	16063
1968	16334
1969	16604
1970	16884
1971	17162
1972	17414
1973	17658
1974	17896
1975	18119
1976	18382
1977	18690
1978	18980
1979	19190
1980	19294
1981	19328
1982	19341
1983	19353
1984	19428
1985	19613
1986	19805
1987	19976
1988	20174
1989	20352
1990	20492
1991	20577
1992	20595
1993	20591
1994	20580
1995	20584
1996	20617
1997	20665
1998	20747
1999	20879
2000	21025
2001	21233
2002	21522
2003	21833
2004	22186
2005	22538
2006	22800
2007	23004
2008	23287
2009	23677
2010	24062
2011	24618
2012	25370
2013	26033
2014	26615
2015	27184
2016	27880
2017	28399
2018	28398
2019	28099
2020	27891
2021	28026
2022	28493
2023	29194