Grade A - Upper Middle Class - The chief income earner's occupation is higher managerial, administrative or professional.
Grade B - Middle Class - The chief income earner's occupation is intermediate managerial, administrative or professional.
Grade C1 - Lower Middle Class - The chief income earner's occupation is supervisory or clerical and junior managerial, administrative or professional.
Grade C2 - Skilled Working Class - The chief income earner is a skilled manual worker.
Grade D - Working Class - The chief income earner is a semi or unskilled manual worker.
Grade E - Those at the lowest levels of subsistence - The chief income earner is a low grade worker, pensioner or depends on the welfare state for income.
