| Value | Category | Cases | |
|---|---|---|---|
| 1970 | 1 |
1.9%
|
|
| 1976 | 1 |
1.9%
|
|
| 1984 | 1 |
1.9%
|
|
| 1990 | 1 |
1.9%
|
|
| 1993 | 1 |
1.9%
|
|
| 1995 | 2 |
3.8%
|
|
| 1997 | 1 |
1.9%
|
|
| 1999 | 1 |
1.9%
|
|
| 2000 | 3 |
5.7%
|
|
| 2002 | 1 |
1.9%
|
|
| 2003 | 3 |
5.7%
|
|
| 2004 | 2 |
3.8%
|
|
| 2005 | 5 |
9.4%
|
|
| 2007 | 6 |
11.3%
|
|
| 2008 | 2 |
3.8%
|
|
| 2009 | 3 |
5.7%
|
|
| 2010 | 1 |
1.9%
|
|
| 2011 | 2 |
3.8%
|
|
| 2012 | 3 |
5.7%
|
|
| 2013 | 1 |
1.9%
|
|
| 2015 | 1 |
1.9%
|
|
| 9998 | don't know | 11 |
20.8%
|
| Sysmiss | 44561 |