| Value | Category | Cases | |
|---|---|---|---|
| 1 | Before 1945 | 194 |
2.9%
|
| 2 | 1945-1960 | 503 |
7.5%
|
| 3 | 1961-1980 | 1585 |
23.8%
|
| 4 | 1981-1990 | 1718 |
25.8%
|
| 5 | After 1990 | 2671 |
40%
|