| Value |
Category |
| -999 |
Don't know |
| -888 |
Refuse to answer |
| -777 |
Not applicable |
| -666 |
Other (please specify) |
| 1 |
Day |
| 2 |
Week |
| 3 |
Two weeks |
| 4 |
Month |
| 5 |
Year |
| 11 |
.R |
| Sysmiss |
|
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.