Year	Number
1970	2589800
1971	2847200
1972	2900000
1973	3299800
1974	3830100
1975	4279000
1976	5416400
1977	5693100
1978	6456000
1979	7333900
1980	8054300
1981	8800000
1982	8987200
1983	9138600
1984	8906500
1985	9315600
1986	8586600
1987	8136900
1988	8313100
1989	7581600
1990	7398600
1991	6057800
1992	5674400
1993	5354400
1994	5857800
1995	5618900
1996	5427100
1997	5219400
1998	5677400
1999	5720100
2000	5605843
2001	5129614
2010	17819048.65930576
2011	20387700.772886455
2012	20515501.676293015
2013	19925850.818
2014	19349770.895975728
2015	21230480
2016	20633300
2017	21624757.049999997
2018	28768397.360006243
2019	28357862.062200513
2020	10279740.062
2021	15075193.281000001