SAPS data are available for various types of administrative units at a variety of spatial scales. The most important types of area include:
The CSO allocates a unique identifying code to each area. However, the codes tend to change from census to census, reflecting both changes in the numbering scheme and boundary changes in the administrative areas themselves.
It is not necessary to know the areas codes to run PC Census Read, but it is necessary to know something about the codes in order to interpret the results. The output from PC Census Read includes either a 5-digit area identifier (if the data are in comma delimited format) or the full 4-, 7- or 9-part CSO area header (if headers are requested with fixed-format data).
The 5-digit area identifiers and the area headers always contain a county identifier code. However, the original CSO county codes tend to change from one census to the next, so PC Census Read converts the original codes to a standardised county code to facilitate easier temporal comparisons. The other components within the 5-digit area identifiers and the area headers identify sub-county divisions, such as Urban and Rural Districts or DEDs. These codes are not modified by PC Census Read.
The codes allocated to specific sub-areas tend to remain fairly stable from one census to the next, but there is no guarantee that a particular code always refers to the same area or that the area has the same boundaries as at the previous census. If extracting data for areas at a sub-county level, it is suggested that you compare the total population of the area (i.e. variable 1) with the total population of the area in published census volumes. If the total population is correct, then it can generally be assumed that the area has been correctly identified. You should also consult the explanatory notes in the published volumes to see if there is any reference to boundary changes (although changes in the smaller spatial units will not necessarily be noted).
These pages contain lists of the codes used for varous types of areas in some census years, but a complete list of codes for all area types is unfortunately not available for every census year. Please consult the area code index for more information.