Low income - the low income limit is often referred to as the "breadline" colloquially. A number of methods are used for calculating low income. A commonly used method is to define all persons that have a net income per consumption unit that is less than 50 or 60 per cent of the median income for all persons, as belonging to a low income group. The number of persons with a low income will vary according to which equivalence scale is applied to calculate income per consumption unit.