| Value | Category | Cases | |
|---|---|---|---|
| -3 | Not applicable; Mother unknown | 7 |
0.6%
|
| -2 | No answer | 14 |
1.1%
|
| -1 | Don't know | 37 |
3%
|
| 1 | Lower | 320 |
26.2%
|
| 2 | Middle | 400 |
32.7%
|
| 3 | Higher | 445 |
36.4%
|