| Value | Category | Cases | |
|---|---|---|---|
| -9 | NIU (not in universe) | 25 |
0.9%
|
| 1 | easy to use method | 1145 |
40.6%
|
| 2 | hard to use method | 1640 |
58.1%
|
| 98 | don't know | 12 |
0.4%
|
| 9999995 | missing:impute | 0 |
0%
|