Year	Number
1971	57829
1972	67230
1973	79055
1978	105368
1980	143556
1981	190702
1982	139784
1983	131918
1984	170545
1985	151759
1986	178910
1987	179338
1988	156200
1989	178868
1990	171156
1991	187436
1992	218987
1998	291708
1999	300480
2000	354984
2001	413695
2002	461825
2008	646180
2009	711232
2010	850334
2011	884982
2016	2034150