Year 	 Pct
1960 	 62.8 
1964 	 61.9 
1968 	 60.9 
1972 	 55.2 
1976 	 53.5 
1980 	 54.0
1984 	 53.1
1988 	 50.2
1992 	 55.9
1996 	 49.0