81% (1980)

75% (1986)

68% (1987)

66% (1993)

57% (1989)

68% (1981)

61% (1995)

56% (1991)

62% (2005)

52% (1986)

72% (1987)

68% (1983)

69% (1982)

68% (1982)

59% (1992)

56% (1980)

65% (1984)

35% (1978)

0% (2012)

68% (2015)