| Value |
Category |
| 0 |
None or very few (0-10) |
| 1 |
Enough to fill a shelf (11-25) |
| 2 |
Enough to fill a bookcase (25-100) |
| 3 |
Enough to fill >1 bookcase (more than 100) |
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.