Year	Total
1971	20810
1972	26140
1973	30870
1974	34390
1975	36110
1976	37150
1977	40330
1978	55630
1979	63710
1980	67240
1981	70590
1982	72740
1983	71450
1984	75150
1985	112200
1986	122800
1987	150200
1988	163400
1989	171500
1990	196000
1991	198800
1992	188500
1993	194200
1994	156200
1995	143900
1996	175300
1997	179300
1998	165300
1999	183600
2000	194300
2001	163700
2002	138500
2003	149700
2004	120500
2005	147700
2006	178000
2007	190400
2008	197000
2009	240500
2010	255000