| Value |
Category |
| 1 |
1970 |
| 2 |
1980 |
| 3 |
1989 |
| 4 |
1992 |
| 5 |
1995 |
| 6 |
1996 |
| 7 |
1998 |
| 8 |
1999 |
| 9 |
2000 |
| 10 |
2001 |
| 11 |
2002 |
| 12 |
2003 |
| 13 |
2004 |
| 14 |
2005 |
| 15 |
2006 |
| 16 |
2007 |
| 17 |
2008 |
| 18 |
2009 |
| 19 |
2010 |
| 20 |
2012 |
| 21 |
2013 |
| 22 |
2014 |
| 23 |
2015 |
| 24 |
2016 |
| 25 |
2017 |
| 26 |
2018 |
| 27 |
2019 |
| 28 |
2020 |
| 29 |
2021 |
| 30 |
Don't know |
| 31 |
Refused to answer |
| 32 |
Outlier set to missing |
| 33 |
Inconsistency set to missing |
| 34 |
Not applicable |
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.