Year Years 1960 3.514 1961 3.711 1962 5.353 1963 6.381 1964 5.597 1965 5.041 1966 3.816 1967 3.947 1968 5.227 1969 5.638 1970 5.788 1971 5.594 1972 5.695 1973 5.847 1974 5.494 1975 5.236 1976 5.185 1977 4.83 1978 3.668 1979 2.797 1980 2.037 1981 1.759 1982 1.173 1983 0.7163 1984 0.3157 1985 0.1489 1986 0.8392 1987 1.841 1988 1.506 1989 1.04 1990 1.669 1991 1.644 1992 1.858 1993 1.831 1994 2.509 1995 2.942 1996 2.982 1997 2.39 1998 2.474 1999 2.796 2000 3.005 2001 2.326 2002 1.711 2003 1.417 2004 1.216