Question
The data for NHS and Census 2011 for Woodstock, Ontario shows that the Census Agglomeration has about 400 more people than does the Population Centre, and they are mapped differently. Since the CA was larger (in terms of geography), it’s easy to accept that the population is higher. But, since I didn’t know what the Population Centre was, I went to the Illustrated Glossary (http://www.statcan.gc.ca/pub/92-195-x/2011001/geo/pop/def-eng.htm) and found that “Population centre population includes all population living in the cores, secondary cores and fringes of census metropolitan areas (CMAs) and census agglomerations (CAs), as well as the population living in population centres outside CMAs and CAs.”
Why are there more people in the Woodstock Ontario census agglomeration than in the Woodstock Ontario population centre, and why aren’t the boundaries the same?
Answer
The census explains that – we are looking for a more detailed comparison between the two, but population centres are based on contiguous (connected) blocks, whereas CMAs and CAs are based on Census Subdivisions (CSDs) which are much larger and can include both urban and rural areas.
So Woodstock, Ontario Census Agglomeration has a higher count as it can include one or more rural areas in it, while Population Centre is “urban” only.
