Definition
Education in single years. This variable is constructed from the educational level (HV106) and the grade at that level (HV107) as follows:
HV106 = > HV108
0 = > 0
1 = > HV107
2 = > HV107+x
3 = > HV107+y
9 = > 99
x = years to complete primary education
y = years to complete primary and secondary education
where both x and y are country-specific.