Year	Number
1965	20055
1966	20888
1967	21624
1968	22420
1969	23169
1970	23782
1971	24336
1972	27503
1973	24461
1974	24378
1975	25246
1976	25906
1977	26210
1978	26475
1979	26733
1980	26512
1981	26976
1982	26941
1983	26082
1984	25405
1985	24854
1986	24541
1987	24460
1988	24824
1989	25292
1990	25762
1991	26253
1992	26676
1993	28748
1994	24454
1995	24303
1996	26836
1997	25580
1998	24361
1999	24327
2000	24583
2001	24614
2002	24841
2003	25107
2004	25301
2005	25509
2006	25423
2007	25062
2008	24653
2009	24346
2010	24299
2011	23812
2012	22810
2013	21914
2014	21115
2015	20371
2016	19282
2017	18116
2018	17341
2019	16895
2020	16598
2021	16247
2022	15871