Year	Number
1970	283004.6
1971	288990.3
1972	303086.5
1973	332278.7
1974	339708.7
1975	329588.9
1976	336718.7
1977	504388.3
1978	516442.3
1979	591883.1
1980	659817.9
1981	529133.8
1982	630802.2
1983	650002
1984	697418.8
1985	736874.9
1986	793281.9
1987	863954.8
1988	896138.4
1989	951684.8
1990	959228.3
1991	966602.5
1992	987665.4
1993	1005579
1994	1039370
1995	982587.9
1996	950396.5
1997	1002860
1998	922250
1999	821729
2000	879868.3
2001	804607.2
2002	919815.3
2003	1014081
2004	1144853
2005	1210429
2006	1384747
2007	1461925
2008	1657405
2009	1832700
2010	1996824
2011	2170853
2012	2389856
2013	2506394
2014	2655769
2015	2861058
2016	2873928
2017	3413483
2018	3655848