| Value |
Category |
| 0 |
IF NEVER, |
| 98 |
IF DON'T KNOW, |
| 1970 |
|
| 1974 |
|
| 1988 |
|
| 1989 |
|
| 1990 |
|
| 1996 |
|
| 1997 |
|
| 1998 |
|
| 1999 |
|
| 2000 |
|
| 2001 |
|
| 2002 |
|
| 2003 |
|
| 2004 |
|
| 2005 |
|
| 2006 |
|
| 2007 |
|
| 2008 |
|
| 2009 |
|
| Sysmiss |
|
Warning: these figures indicate the number of cases found in the data file. They cannot be interpreted as summary statistics of the population of interest.