| Year | Value | | 2004 | 6,428,701 | | 2003 | 5,886,037 | | 2002 | 6,322,432 | | 2001 | 6,382,092 | | 2000 | 5,922,623 | | 1999 | 5,767,700 | | 1998 | 5,946,600 | | 1997 | 6,236,400 | | 1996 | 5,892,000 | | 1995 | 5,689,300 | | 1994 | 5,381,000 | | 1993 | 5,077,900 | | 1992 | 4,826,800 | | 1991 | 4,582,000 | | 1990 | 4,840,300 | | 1989 | 4,720,600 | | 1988 | 4,376,700 | | 1987 | 4,148,100 | | 1986 | 3,834,000 | | 1985 | 3,494,000 | | 1984 | 3,229,200 | | 1983 | 3,947,700 | | 1982 | 3,536,900 | | 1981 | 3,065,000 | | 1980 | 3,329,700 | | 1979 | 3,556,200 | | 1978 | 3,117,200 | | 1977 | 2,946,800 | | 1976 | 2,795,700 | | 1975 | 2,518,100 | | 1974 | 2,401,900 | | 1973 | 2,409,000 | | 1972 | 2,284,900 | | 1971 | 2,056,800 | | 1970 | 1,775,300 |
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