Year	Number
1973	1900
1974	1723
1975	1916
1976	2044
1977	2010
1978	2235
1979	2345
1980	2479
1981	2577
1982	2543
1983	2736
1984	2910
1985	2892
1986	2856
1987	2906
1988	2887
1989	2882
1990	3059
1991	3092
1992	3085
1993	3312
1994	3386
1995	3536
2011	7679
2012	8117
2013	8413
2014	8896
2015	9219
2016	9303
2017	9332
2018	9551
2019	9460
2020	9112
2022	8683