The theoretical and conceptual considerations for developing the main structure of the classification were applied in conjunction with other considerations such as the feasibility of the classification for collecting data from both statistical and administrative collections, the ease of implementing the classification in statistical and administrative systems, the analytical usefulness of data collected within the framework of the classification, and the structural and statistical balance of the classification.
An important consideration in developing any classification for statistical purposes is to achieve a structure that is physically and statistically balanced. This is necessary to allow the classification to fulfil its functions in a way that is useful and practical for presenting and analysing statistical data, especially from sample surveys.
Physical balance is achieved by developing a classification that has manageable and roughly similar numbers of sub-categories within each category at a particular level. The desire to achieve this result is, of course, tempered by the need to accurately reflect the real world.
Statistical balance means that no major or minor group should represent an inordinate number of observations (say, country of birth responses), and that each major and minor group should represent significant numbers of observations. Thus, a classification used for the dissemination of statistics should not have categories at the same level in its hierarchy which are too disparate in their population size. This allows the classification to be used effectively for the cross-tabulation of aggregate data and the dissemination of data from sample surveys. An important use of the SACC is to classify birthplace data. Birthplace data from the 1996 Census of Population and Housing were used to test and modify the structure of the SACC on the basis of statistical balance.
Application of the classification criteria in a straightforward manner generally led to a harmonious and symmetrical main classification structure. However, considerations of practicality, usefulness and statistical balance were also used in developing the structure in certain areas, such as in splitting Europe into two major groups (one in the first edition, ASCCSS), and in combining the two American continents to form one major group (two in the first edition, ASCCSS). The consideration of these additional factors did not impinge on correct application of the classification criteria.