Year	Total
1971	7354
1972	7524
1973	7873
1974	8296
1975	8049
1976	8359
1977	9232
1978	12290
1979	14190
1980	14470
1981	14570
1982	14950
1983	13580
1984	14620
1985	14660
1986	13940
1987	12900
1988	11560
1989	10790
1990	10600
1991	9829
1992	9597
1993	10070
1994	10110
1995	10020
1996	9959
1997	9744
1998	9786
1999	9527
2000	9361
2001	9414
2002	9291
2003	9506
2004	9608
2005	10910
2006	11650
2007	12480
2008	12650
2009	15140