The 2006 Census counted 31,612,897 people in Canada during the national enumeration with reference day May 16, 2006. These counts are lower than the population estimate of 32,623,490 published as of July 1 2006. The difference between the two figures is not unexpected and is similar to that which was experienced in 2001.
More specifically, this difference is primarily due to net census undercoverage. While the census strives to enumerate the entire population on Census Day, inevitably, a few people are not counted (for example, they were away during the enumeration period) and even fewer are counted twice (for example, students living away from home enumerated by both themselves and their parents).
To determine how many individuals were missed or counted more than once, Statistics Canada conducts postcensal coverage studies of a representative sample of individuals. Results of these studies in combination with the census counts are used to produce current population estimates which take into account net undercoverage. In 2001, after these adjustments, the population estimate for Canada was 3.1% higher than the population enumerated in the census.
Postcensal coverage study results are usually available two (2) years after enumeration date. For the 2006 Census, preliminary postcensal study results will be released in March 2008. Final estimates of coverage error will be made available in September 2008. They will be used to revise and update the population estimates based on the 2006 Census results. Consequently, a series of revised population estimates for the period 2001 to 2008 will be disseminated in September 2008.
The census counts and the population estimates play key and complementary roles as sources of information on population.
The census provides unique, detailed statistical data at a single point in time on the demographic, social and economic conditions of the population. The census tells us not only about Canada but about the cities, communities and people that make up each province and territory. Because the census measures such a wide range of standardized and nationally comparable statistics, it is a unique source of cross-classified data. For example, the census can provide information such as employment by industry and occupation. It can also provide socio-economic information about specific groups such as Aboriginal peoples, visible minorities and language groups. In general, studying trends over time is not affected by net census undercoverage to the extent that it does not vary much from one census to the next.
Population estimates are used to calculate the major federal transfers to the provinces and territories (for example, through such programs as Equalization, Canada Health and Social Transfer, the Health Reform Transfer and Territorial Formula Financing). The population estimates are adjusted for net census undercoverage, as even a small error in the estimates could result in a misallocation of millions of dollars. It is estimated that in 2006-2007, support through major transfers to provinces and territories will be approximately $62.1 billion. The estimates also play an important role as population benchmarks in the production of current socio-economic indicators such as vital rates, unemployment rates and school enrolment rates. In addition, estimates are used to weight Statistics Canada surveys, including the Labour Force Survey, the Household Facilities Survey, the General Social Survey and the Survey of Labour and Income Dynamics.