Literal question
How much did you derive as income, including overtime pay, from your main job/business for last month?
Interviewer instructions
If the respondent is a paid employee, ask for his gross pay, i.e. before tax and other deductions. Gross pay includes all allowances and also overtime payments. For a person receiving pay at the end of a day, week or fortnight, work out an estimate for the month. For persons operating their own businesses or trades, enter the net income, i.e. after deduction of expenses.