Year	Number
1970	93600
1971	93600
1972	93600
1973	93600
1974	93600
1975	138000
1976	141000
1977	153000
1978	196938
1979	277288
1980	319576
1981	512205
1982	693799
1983	790711
1984	889966
1985	905909
1986	957357
1987	1003982
1988	1069433
1989	1124681
1990	1234000
1991	1466311
1992	1568370
1993	1614676
1994	1675654
1995	1719412
1996	1796041
1997	1877049
1998	2167037
1999	2706182
2000	2964730
2001	3232925
2002	3417000
2003	3502629
2004	3695133
2005	3844000
2006	3951000
2007	3996000
2008	4100000
2009	4171000
2010	4165750
2011	4633158
2012	4801824
2013	4939715
2015	3746906
2016	4238774
2017	4659836
2018	5387405
2019	5377978
2020	5749058
2021	6594631
2022	6773272
