The spatial framework for which the Census of Canada provides data has evolved, through successive censuses, to meet the need of users. Because of the changing nature of the electoral districts of the early censuses, a more permanent spatial framework, namely, the county, and an equivalent area called the census division, was introduced in the 1921 and 1931 censuses. After World War II, users of census data requested a smaller spatial framework. In. 1951 data were available at the municipality level and, in 1961, all census data taken on a 100 per cent basis were available at the enumeration area level. Currently, the ability to provide census data for user-specified areas is being developed through a geocoding system.