| Value | Category | Cases | |
|---|---|---|---|
| 1975 | 1 |
2.5%
|
|
| 1990 | 2 |
5%
|
|
| 1994 | 1 |
2.5%
|
|
| 1995 | 2 |
5%
|
|
| 1996 | 1 |
2.5%
|
|
| 2000 | 3 |
7.5%
|
|
| 2002 | 2 |
5%
|
|
| 2005 | 2 |
5%
|
|
| 2006 | 2 |
5%
|
|
| 2007 | 1 |
2.5%
|
|
| 2008 | 4 |
10%
|
|
| 2009 | 1 |
2.5%
|
|
| 2011 | 4 |
10%
|
|
| 2012 | 4 |
10%
|
|
| 2013 | 9 |
22.5%
|
|
| 2014 | 1 |
2.5%
|
|
| Sysmiss | .don't know | 0 | |
| Sysmiss | .qre refused | 0 | |
| Sysmiss | .refusal | 0 | |
| Sysmiss | .skip | 0 | |
| Sysmiss | .x. censored | 0 | |
| Sysmiss | 1394 |