| Value | Category | Cases | |
|---|---|---|---|
| -99 | DK | 2 |
0.1%
|
| -88 | Missing | 0 |
0%
|
| -77 | NA | 5 |
0.3%
|
| 1971 | 1 |
0.1%
|
|
| 1972 | 1 |
0.1%
|
|
| 1977 | 17 |
1.1%
|
|
| 1979 | 1 |
0.1%
|
|
| 1987 | 3 |
0.2%
|
|
| 1989 | 1 |
0.1%
|
|
| 1990 | 4 |
0.3%
|
|
| 1991 | 5 |
0.3%
|
|
| 1992 | 5 |
0.3%
|
|
| 1993 | 3 |
0.2%
|
|
| 1994 | 8 |
0.5%
|
|
| 1995 | 45 |
2.9%
|
|
| 1996 | 39 |
2.5%
|
|
| 1997 | 132 |
8.4%
|
|
| 1998 | 205 |
13.1%
|
|
| 1999 | 338 |
21.5%
|
|
| 2000 | 751 |
47.8%
|
|
| 2001 | 4 |
0.3%
|
|
| Sysmiss | 5 |