54% (1985)

53% (1988)

51% (1987)

36% (1989)

40% (1990)

51% (1986)

66% (1987)

54% (1981)

48% (1988)

47% (1986)

46% (1985)

49% (1988)

40% (1982)

58% (1991)

46% (1991)

54% (1980)

44% (1994)

36% (1991)

36% (1988)

45% (1986)