| Value | Category | 
|---|---|
| 1 | don’t know/ no answer | 
| 2 | from conventional tillage to reduced tillage | 
| 3 | from no tillage to reduced tillage | 
| 4 | from conventional tillage to no tillage | 
| 5 | from no tillage to conventional tillage | 
| 6 | from reduced tillage to no tillage | 
| 7 | from reduced to conventional tillage |