About Population Estimates
Revision of Population Figures
Population estimates are periodically revised for a number of reasons, including revisions to the underlying indicator data, methodological improvements and to reflect updated base year data from a new census. Projections are updated annually to reflect the latest estimates based on actual indicator data, as well as any new information on likely future demographic and economic changes (for example, the expectation of a mine closure due to mineral depletion). Census data are never revised except in the event that an error is discovered.
Note: when population data are revised, other measures such as employment rates, GDP per capita and so forth, that use population as a denominator, will be revised also.
Census Population and Estimates in Census years
The Census provides detailed information on the demographic, social and economic conditions of the population at a single point in time. Inevitably, however, some people are not counted (if they did not receive a census questionnaire) and a small number may be counted twice (for example, a student living away from home).
To determine how many individuals were missed, or counted more than once, Statistics Canada conducts post-censal coverage studies of a representative sample of individuals. The results of these studies provide information that is used to adjust the Census counts for the purpose of producing current (quarterly and annual) population estimates, which take into account net under-enumeration in the Census.
For example, in 2006, after adjustment for net under-enumeration, the population estimate for Canada was 2.8 percent higher than the population enumerated in the Census and the population estimate for British Columbia was 2.9 percent higher than the Census count.