Year	Number
1960	-477
1961	-670
1962	-917
1963	-998
1964	-984
1965	-1037
1966	-1373
1967	-1944
1968	-2239
1969	-2274
1970	-2307
1971	-2333
1972	-2357
1973	-2375
1974	-1572
1975	-1654
1976	-1887
1977	-2893
1978	-3071
1979	-3227
1980	-3270
1981	-3483
1982	-4511
1983	-4815
1984	-4975
1985	-5010
1986	-4739
1987	-3812
1988	-4097
1989	-4241
1990	-4286
1991	-3705
1992	-3166
1993	-2944
1994	-2979
1995	-3004
1996	-3003
1997	-2984
1998	-2986
1999	-3001
2000	-3020
2001	-3489
2002	-3772
2003	-3966
2004	-4022
2005	-4040
2006	-3553
2007	-3334
2008	-3244
2009	-3252
2010	-3274
2011	-3246
2012	-3215
2013	-3182
2014	-3161
2015	-3137
2016	-2772
2017	-2824
2018	-2739
2019	-2469
2020	-1060
2021	-882
2022	-1500
2023	-1500