An index of household composition for the assessment and forecasting of housing needs

An indexing method, adopted from mathematical logic, is propounded to express any type of household composition as a single, natural number. Application of the indexing method yields a matrix whose elements denote average numbers of persons in given ages, in households with housing needs for a specified number of rooms. The matrix has similar properties to the household composition matrix introduced recently in connection with the projection of population and households. It is demonstrated that if the matrix is modified so as to fulfill the Stolper‐Samuelson condition, known from economic theory, then a simultaneous projection of population and housing needs can be performed.