in thousands

0

1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986

2

1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986

1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986

0

1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986