| Value | Category |
|---|---|
| 1 | Central heating - monthly expenses |
| 2 | Heating on electricity |
| 3 | Heating on solid fuels (coal, fire wood)-last heating season |
| 4 | Heating on gas-last heating season |
| 5 | Liquid fuels (heating/crude oil)-last heating season |
| 9999998 | REFUSAL |
| 9999999 | DONTKNOW |
| Sysmiss |