Year	Total
1960	1728000000
1961	1894000000
1962	2142000000
1963	2352000000
1964	2602000000
1965	2831000000
1966	3041000000
1967	3324000000
1968	3628000000
1969	3983000000
1970	4415000000
1971	4886000000
1972	5503000000
1973	6071000000
1974	6403000000
1975	6788000000
1976	7379000000
1977	7669000000
1978	8155000000
1979	8386000000
1980	8770000000
1981	7431000000
1982	7334000000
1983	7504000000
1984	7839000000
1985	8323000000
1986	8435000000
1987	11040000000
1988	11320000000
1989	11530000000
1990	11880000000
1991	12600000000
1992	12780000000
1993	13140000000
1994	12980000000
1995	13590000000
1996	14200000000
1997	13890000000
1998	13950000000
1999	14050000000
2000	14200000000
2001	15310000000
2002	15770000000
2003	16900000000
2004	16770000000
2005	17070000000
2006	17010000000
2007	16830000000
2008	16970000000