Year	Total
1971	89020000
1972	205000000
1973	317100000
1974	414100000
1975	602100000
1976	854200000
1977	1300000000
1978	1656000000
1979	2196000000
1980	2775000000
1981	3176000000
1982	3924000000
1983	4463000000
1984	4841000000
1985	5281000000
1986	5639000000
1987	6010000000
1988	6531000000
1989	6714000000
1990	7175000000
1991	7288000000
1992	7850000000
1993	9129000000
1994	9971000000
1995	10560000000
1996	11150000000
1997	11740000000
1998	12340000000
1999	12930000000
2000	13520000000
2001	14110000000
2002	14700000000
2003	16500000000
2004	17460000000
2005	18860000000
2006	21400000000
2007	24680000000
2008	29930000000