20% (2002)

76% (2005)

50% (2011)

75% (2014)

65% (2009)

87% (1997)

70% (2013)

70% (2008)

80% (2004)

50% (1996)

70% (2013)

80% (1999)

50% (1992)

70% (1995)

55% (1990)