Year	Number
1960	-27179
1961	-27959
1962	-28854
1963	-29988
1964	-32153
1965	-34847
1966	-37355
1967	-38972
1968	-39058
1969	-37903
1970	-36078
1971	-34137
1972	-32609
1973	-31895
1974	-31225
1975	-30556
1976	-30002
1977	-29659
1978	-29647
1979	-29890
1980	-30275
1981	-30641
1982	-30852
1983	-30484
1984	-28058
1985	-24137
1986	-19630
1987	-15430
1988	-12126
1989	-8686
1990	-5253
1991	-2214
1992	17
1993	1196
1994	1931
1995	2490
1996	2980
1997	3536
1998	4240
1999	4988
2000	5790
2001	6720
2002	7828
2003	9266
2004	11515
2005	14336
2006	17348
2007	20188
2008	22516
2009	24330
2010	26064
2011	28128
2012	30925
2013	36566
2014	52709
2015	55709
2016	126525
2017	214697
2018	237358
2019	230162
2020	98439
2021	113709
2022	-66850
2023	-71205