Derivation
Derived from census records for persons.
‘Derived household income’ was calculated by adding together all recorded individual incomes of household members, plus the household’s additional income and remittances received. Because individual income was recorded in intervals rather than exact amounts, an approximate amount had to be estimated for the calculations as follows:
• households claiming that they had no income were not adjusted,
• for the first class among those with incomes, the amount was R1 600,
• for the second class, the amount was the midpoint of the class interval,
• for the last class, the amount was R720 000,
• for the other classes, the amount was calculated as the logarithmic mean of the top and bottom of the
given interval.
If ‘Individual income’ was missing for a member of the household aged under 15, the income for the child was set to 0. However, if a member of the household aged 15 years or older had income missing, the ‘Derived household income’ was set to missing as there was insufficient information for the estimate to be reliable. If ‘Additional money generated’ or ‘Remittances received’ were missing, then they were set to 0. Income for the entire household were again converted into categories.