| Value | Category | Cases | |
|---|---|---|---|
| 1993 | 1 |
2.4%
|
|
| 1996 | 1 |
2.4%
|
|
| 1997 | 1 |
2.4%
|
|
| 2003 | 2 |
4.8%
|
|
| 2004 | 2 |
4.8%
|
|
| 2006 | 2 |
4.8%
|
|
| 2007 | 1 |
2.4%
|
|
| 2008 | 4 |
9.5%
|
|
| 2009 | 3 |
7.1%
|
|
| 2010 | 3 |
7.1%
|
|
| 2011 | 2 |
4.8%
|
|
| 2012 | 10 |
23.8%
|
|
| 2013 | 8 |
19%
|
|
| 9998 | year don't know | 2 |
4.8%
|
| Sysmiss | 10874 |