| Value |
Category |
| 0 |
nil |
| 1 |
once |
| 2 |
twice |
| 3 |
three times |
| 4 |
four times |
| 5 |
more than four |
| 999 |
not applicable |
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.