Year	Total
1971	39950
1972	39670
1973	38510
1974	39090
1975	40490
1976	41540
1977	43280
1978	41980
1979	43240
1980	41210
1981	41340
1982	41860
1983	42470
1984	43120
1985	42670
1986	43600
1987	44690
1988	44070
1989	42430
1990	40910
1991	38580
1992	36250
1993	35750
1994	33280
1995	32410
1996	33080
1997	33460
1998	31490
1999	28760
2000	30650
2001	31360
2002	31450
2003	33500
2004	34540
2005	32920
2006	33560
2007	33750
2008	32820
2009	31200
2010	31440