Year	Number
1960	-385
1961	-395
1962	-404
1963	-408
1964	-417
1965	-423
1966	-445
1967	-462
1968	-471
1969	-612
1970	-901
1971	-1031
1972	-952
1973	-844
1974	-682
1975	-406
1976	-39
1977	180
1978	253
1979	302
1980	333
1981	352
1982	375
1983	383
1984	398
1985	397
1986	188
1987	-220
1988	-430
1989	-475
1990	-529
1991	-585
1992	-650
1993	-726
1994	-793
1995	-859
1996	-908
1997	-971
1998	-1065
1999	-1478
2000	-2137
2001	-2511
2002	-2603
2003	-2685
2004	-2745
2005	-2800
2006	-2848
2007	-2901
2008	-2964
2009	-2579
2010	-2225
2011	-1875
2012	-1634
2013	-1603
2014	-1603
2015	-1603
2016	-1603
2017	-1603
2018	-1603
2019	-1603
2020	-808
2021	-808
2022	-1600
2023	-1600