| Value | Category | Cases | |
|---|---|---|---|
| 1 | Electricity | 6 |
1.5%
|
| 2 | Paraffin | 4 |
1%
|
| 3 | Wood | 347 |
87.2%
|
| 4 | Coal | 5 |
1.3%
|
| 5 | Charcoal | 32 |
8%
|
| 6 | Sawdust | 0 |
0%
|
| 7 | Gas | 4 |
1%
|
| 8 | Other, specify | 0 |
0%
|
| Sysmiss | 6 |