Year	Total
1971	852200000
1972	1053000000
1973	1178000000
1974	1196000000
1975	1275000000
1976	1277000000
1977	1438000000
1978	1565000000
1979	1668000000
1980	1786000000
1981	1910000000
1982	1957000000
1983	1805000000
1984	1641000000
1985	1996000000
1986	2330000000
1987	2501000000
1988	2513000000
1989	2472000000
1990	4332000000
1991	4545000000
1992	4950000000
1993	5378000000
1994	5866000000
1995	6303000000
1996	7043000000
1997	5259000000
1998	5732000000
1999	5975000000
2000	6182000000
2001	6908000000
2002	7163000000
2003	7341000000
2004	7835000000
2005	8285000000
2006	8548000000
2007	8904000000
2008	8751000000