| Value | Category | Cases | |
|---|---|---|---|
| 1 | Never | 25 |
1.1%
|
| 2 | Once a term | 17 |
0.7%
|
| 3 | Once a month | 132 |
5.5%
|
| 4 | Once a week | 924 |
38.8%
|
| 5 | Nearly every day | 1179 |
49.5%
|
| 98 | Other | 103 |
4.3%
|
| 99 | No books | 0 |
0%
|
| Sysmiss | 947 |