1978 |
67%
|
2017 |
62%
|
1980 |
68%
|
1984 |
57%
|
1999 |
81%
|
2000 |
81%
|
1975 |
65%
|
2006 |
76%
|
1995 |
80%
|
1993 |
64%
|
2011 |
80%
|
1989 |
46%
|
1991 |
64%
|
1994 |
66%
|
1991 |
41%
|
1992 |
34%
|
2012 |
30%
|
1996 |
46%
|