| Value | Category | Cases | |
|---|---|---|---|
| -8 | other error | 0 |
0%
|
| -7 | filter error | 0 |
0%
|
| -4 | number of hours varies greatly | 62 |
0.5%
|
| -3 | inapplicable | 12999 |
99.4%
|
| -2 | no answer | 1 |
0%
|
| -1 | does not know | 18 |
0.1%
|