Year	Number
1960	-7545
1961	-8018
1962	-8475
1963	-8917
1964	-9418
1965	-9943
1966	-10478
1967	-10991
1968	-11483
1969	-12540
1970	-13518
1971	-14162
1972	-14342
1973	-14106
1974	-13514
1975	-13171
1976	-13345
1977	-13738
1978	-13949
1979	-14748
1980	-17487
1981	-19810
1982	-20884
1983	-21584
1984	-22238
1985	-23385
1986	-24769
1987	-25852
1988	-26560
1989	-26983
1990	-27399
1991	-29349
1992	-29822
1993	-30265
1994	-30721
1995	-29610
1996	-29875
1997	-30020
1998	-30030
1999	-30104
2000	-30231
2001	-30371
2002	-30477
2003	-30549
2004	-30709
2005	-30883
2006	-30977
2007	-30898
2008	-30605
2009	-30468
2010	-30489
2011	-30572
2012	-30615
2013	-30563
2014	-30449
2015	-30310
2016	-30181
2017	-30055
2018	-29944
2019	-29830
2020	-14966
2021	-14966
2022	-29294
2023	-29099