Year	Number
1960	12000
1961	10000
1962	10000
1963	9500
1964	9500
1965	9000
1966	8500
1967	8000
1968	8000
1969	8000
1970	8524
1971	8600
1972	8830
1973	8400
1974	8015
1975	7850
1976	7900
1977	8000
1978	8000
1979	10000
1980	12000
1981	13000
1982	14000
1983	14500
1984	15000
1985	15500
1986	16000
1987	24000
1988	25963
1989	16971
1990	17337
1991	19020
1992	29721
1993	43521
1994	62152
1995	79949
1996	102573
1997	118057
1998	131481
1999	138633
2000	146174
2001	151919
2002	148349
2003	140877
2004	126792
2005	118172
2006	100565
2007	86576
2008	77589
2009	75996
2010	74948
2011	74587
2012	71893
2013	74700
2014	82483
2015	88518
2016	101727
2017	103843
2018	101824
2019	94417
2020	95897
2021	99585
2022	237368
2023	237767