| Value |
Category |
| 1 |
1945 or before |
| 2 |
1946-1960 |
| 3 |
1961-1970 |
| 4 |
1971-1980 |
| 5 |
1981-1990 |
| 6 |
1991-1994 |
| 7 |
1995-1998 |
| 8 |
1999-2002 |
| 9 |
NIU (not in universe) |
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.