Year	Number
1970	8349805.5
1971	8123516.5
1972	7853896
1973	7582555
1974	7458905.5
1975	7477324.5
1976	7624137
1977	7791790.5
1978	7904807.5
1979	7777054
1980	7634435.5
1981	7603608
1982	7834006
1983	8068926.5
1984	8272237.5
1985	8409692
1986	8425066
1987	8478423
1988	8414528
1989	8279274.5
1990	8040246.5
1991	7881152.5
1992	7823110.5
1993	7812640
1994	7809599
1995	7775469
1996	7742684
1997	7796121
1998	7668135
1999	7386684
2000	7118397
2001	6843022
2002	6548818
2003	6273652
2004	6054675.5
2005	5777246
2006	5534494
2007	5402565
2008	5199063
2009	5077475
2010	4984701
2011	4908890
2012	4885121
2013	5061141
2014	5068456.5
2015	5111040
2016	5199548
2017	5289611
2018	5292234
2019	5298720
2020	4268968
2021	4387560.5
2022	4379113.5