| Value | Category | Cases | |
|---|---|---|---|
| 1977 | 1 |
0%
|
|
| 1978 | 2 |
0.1%
|
|
| 1979 | 1 |
0%
|
|
| 1980 | 13 |
0.4%
|
|
| 1981 | 14 |
0.4%
|
|
| 1982 | 23 |
0.7%
|
|
| 1983 | 28 |
0.9%
|
|
| 1984 | 23 |
0.7%
|
|
| 1985 | 33 |
1%
|
|
| 1986 | 44 |
1.4%
|
|
| 1987 | 43 |
1.3%
|
|
| 1988 | 47 |
1.5%
|
|
| 1989 | 45 |
1.4%
|
|
| 1990 | 43 |
1.3%
|
|
| 1991 | 42 |
1.3%
|
|
| 1992 | 40 |
1.3%
|
|
| 1993 | 41 |
1.3%
|
|
| 1994 | 37 |
1.2%
|
|
| 1995 | 38 |
1.2%
|
|
| 1996 | 41 |
1.3%
|
|
| 1997 | 35 |
1.1%
|
|
| 1998 | 39 |
1.2%
|
|
| 1999 | 54 |
1.7%
|
|
| 2000 | 58 |
1.8%
|
|
| 2001 | 46 |
1.4%
|
|
| 2002 | 48 |
1.5%
|
|
| 2003 | 55 |
1.7%
|
|
| 2004 | 48 |
1.5%
|
|
| 2005 | 73 |
2.3%
|
|
| 2006 | 76 |
2.4%
|
|
| 2007 | 80 |
2.5%
|
|
| 2008 | 85 |
2.7%
|
|
| 2009 | 90 |
2.8%
|
|
| 2010 | 101 |
3.2%
|
|
| 2011 | 90 |
2.8%
|
|
| 2012 | 101 |
3.2%
|
|
| 2013 | 101 |
3.2%
|
|
| 2014 | 116 |
3.6%
|
|
| 2015 | 133 |
4.2%
|
|
| 2016 | 86 |
2.7%
|
|
| 2017 | 92 |
2.9%
|
|
| 2018 | 57 |
1.8%
|
|
| 2019 | 11 |
0.3%
|
|
| 9997 | INCONSISTENT | 2 |
0.1%
|
| 9998 | DK | 17 |
0.5%
|
| 9999 | NO RESPONSE | 7 |
0.2%
|
| Sysmiss | 892 |
27.9%
|