| Value | Category | Cases | |
|---|---|---|---|
| 1949 | 38 |
8.1%
|
|
| 1950 | 16 |
3.4%
|
|
| 1960 | 41 |
8.8%
|
|
| 1970 | 82 |
17.5%
|
|
| 1980 | 41 |
8.8%
|
|
| 1990 | 45 |
9.6%
|
|
| 2000 | 159 |
34%
|
|
| 2010 | 46 |
9.8%
|
|
| Sysmiss | 5 |