25% (1991)

35% (2005)

32% (1989)

47% (2007)

34% (2004)

34% (1995)

55% (2005)

39% (1987)

46% (1990)

23% (2006)

38% (1997)

36% (1994)

50% (1990)

60% (1990)

32% (1990)

48% (1993)