Year	Total
1971	1350000000
1972	1429000000
1973	1543000000
1974	1617000000
1975	1620000000
1976	1716000000
1977	1816000000
1978	1864000000
1979	2066000000
1980	2385000000
1981	2435000000
1982	2569000000
1983	2657000000
1984	2773000000
1985	2950000000
1986	3062000000
1987	3215000000
1988	3316000000
1989	3594000000
1990	3679000000
1991	3803000000
1992	3702000000
1993	4138000000
1994	4490000000
1995	4999000000
1996	5452000000
1997	5508000000
1998	5595000000
1999	5673000000
2000	5420000000
2001	5223000000
2002	5158000000
2003	5040000000
2004	4818000000
2005	4702000000
2006	4578000000
2007	4603000000
2008	4532000000