| Value | Category | Cases | |
|---|---|---|---|
| 0 | never | 1185 |
96%
|
| 98 | DON'T KNOW | 12 |
1%
|
| 1998 | 1 |
0.1%
|
|
| 2000 | 1 |
0.1%
|
|
| 2006 | 1 |
0.1%
|
|
| 2009 | 2 |
0.2%
|
|
| 2011 | 2 |
0.2%
|
|
| 2012 | 14 |
1.1%
|
|
| 2013 | 15 |
1.2%
|
|
| 2014 | 1 |
0.1%
|
|
| 2015 | 1 |
0.1%
|
|
| Sysmiss | 491 |