| Value | Category | Cases | |
|---|---|---|---|
| 1 | Do not know | 1136 |
45.2%
|
| 1960 | 1 |
0%
|
|
| 1964 | 2 |
0.1%
|
|
| 1973 | 4 |
0.2%
|
|
| 1974 | 4 |
0.2%
|
|
| 1975 | 9 |
0.4%
|
|
| 1978 | 8 |
0.3%
|
|
| 1980 | 41 |
1.6%
|
|
| 1981 | 5 |
0.2%
|
|
| 1983 | 2 |
0.1%
|
|
| 1984 | 5 |
0.2%
|
|
| 1985 | 3 |
0.1%
|
|
| 1986 | 18 |
0.7%
|
|
| 1988 | 10 |
0.4%
|
|
| 1989 | 15 |
0.6%
|
|
| 1990 | 34 |
1.4%
|
|
| 1992 | 6 |
0.2%
|
|
| 1993 | 7 |
0.3%
|
|
| 1994 | 32 |
1.3%
|
|
| 1996 | 18 |
0.7%
|
|
| 1997 | 12 |
0.5%
|
|
| 1998 | 34 |
1.4%
|
|
| 1999 | 43 |
1.7%
|
|
| 2000 | 21 |
0.8%
|
|
| 2001 | 18 |
0.7%
|
|
| 2002 | 17 |
0.7%
|
|
| 2003 | 32 |
1.3%
|
|
| 2004 | 48 |
1.9%
|
|
| 2005 | 16 |
0.6%
|
|
| 2006 | 27 |
1.1%
|
|
| 2007 | 74 |
2.9%
|
|
| 2008 | 108 |
4.3%
|
|
| 2009 | 115 |
4.6%
|
|
| 2010 | 143 |
5.7%
|
|
| 2011 | 126 |
5%
|
|
| 2012 | 90 |
3.6%
|
|
| 2013 | 132 |
5.3%
|
|
| 2014 | 97 |
3.9%
|
|
| Sysmiss | 13812 |