Year Total 1971 619.6 1972 683.1 1973 687.7 1974 733.1 1975 747 1976 807.8 1977 898.5 1978 862.9 1979 895.7 1980 877.9 1981 812.1 1982 788.8 1983 836.3 1984 879 1985 873.6 1986 891.4 1987 812.4 1988 831.2 1989 758.1 1990 773.2 1991 834.5 1992 815.9 1993 789.1 1994 849.1 1995 830.9 1996 877 1997 841.5 1998 764.9 1999 615.1 2000 570.7 2001 583.6 2002 585.7 2003 639 2004 680.4 2005 610.3 2006 629 2007 638.9 2008 633.2 2009 781.6