| Value | Category | Cases | |
|---|---|---|---|
| -9 | NIU (not in universe) | 4 |
0.1%
|
| 1 | easy to obtain method | 2723 |
96.5%
|
| 2 | hard to obtain method | 89 |
3.2%
|
| 8 | don't know/unsure | 6 |
0.2%
|
| 9999995 | missing:impute | 0 |
0%
|