Year	Number
1970	261137.1
1971	266341.9
1972	299739.7
1973	328272.3
1974	352084
1975	402161.4
1976	416987
1977	453214.1
1978	489910.5
1979	536532.9
1980	576927.5
1981	600641.3
1982	640691.4
1983	687667.6
1984	736750.1
1985	793760.4
1986	820822.3
1987	859602.5
1988	939691.8
1989	947585.5
1990	972760.6
1991	994519.7
1992	1031790
1993	1095173
1994	1176866
1995	1251483
1996	1267396
1997	1330800
1998	1279734
1999	1301469
2000	1352231
2001	1392720
2002	1446194
2003	1501572
2004	1591270
2005	1690962
2006	1791105
2007	1880359
2008	2143605
2009	2379475
2010	2614375
2011	2669222
2012	2787668
2013	2841414
2014	2985985
2015	3075768
2016	3087223
2017	3144649
2018	3357939