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10 Population Estimates

Population Estimates

Population Estimates: PHU, County, and Municipality Level
Original source: Statistics Canada
Distributed by: Ontario Ministry of Health and Long-term Care: IntelliHEALTH Ontario
Suggested citation (see Data Citation Notes):
Population Estimates [years], Ontario Ministry of Health and Long-Term Care, IntelliHEALTH Ontario, Date Extracted: [date]

Population Estimates: LHIN Level
Original source: 1986–2000, Statistics Canada; 2001–onwards, Ontario Ministry of Finance
Distributed by: Ontario Ministry of Health and Long-Term Care: IntelliHEALTH Ontario
Suggested citation (see Data Citation Notes):
Population Estimates [years], Ontario Ministry of Health and Long-Term Care, IntelliHEALTH Ontario, Date Extracted [date]

Data Notes

  • Population estimates for PHUs, Counties and municipalities in IntelliHealth are derived from population estimates at the census sub-division (CSD) level for July 1st of each year, produced by Demography Division, Statistics Canada.
  • The counties and municipalities in IntelliHealth are based on the MOHLTC residence coding classification and do not correspond exactly to the Statistics Canada CDs and CSDs in some cases. In particular, reserves that are split across two counties by Statistics Canada are assigned to one county by the MOHLTC.  Also, unorganized CSDs in the north are split into several unorganized municipalities in the residence coding system.  In these cases, the CSD population is assigned to one of the municipalities with the result that the remaining municipalities would have zero population when queried.
  • The population estimates are based on the 1986, 1991, 1996, 2001, and 2006 census counts adjusted for net undercoverage. Population estimates for 1986 to 2005 are final intercensal estimates that are interpolated using the adjusted census counts for the census years around the year that the estimates are for. Population estimates for 2006 onwards are post-censal estimates based on the 2006 census counts adjusted for net undercoverage and changes in the population between Census Day and July 1.  CSD postcensal estimates are extrapolated by applying the growth rates by age and sex of each census division (CD) to the adjusted census counts of each census subdivision (CSD) in that CD.  CD populations are estimated by the demographic component method and use data on births, deaths, international migration and internal migration when these data are available.
  • CSD populations are estimated in three steps1:   
    • CD populations are estimated using the component method
    • The growth rates for the CDs are calculated by age and sex
    • The growth rates for each CD are applied to the CSDs within that CD
  • Preliminary estimates using a regression model are released for current years and then revised using the component method.  When Statistics Canada releases preliminary postcensal estimates for the current year, revised post-censal estimates for at least two previous years are also released and IntelliHealth tables are updated. 
  • When the population estimates for a new census year are ready, postcensal estimates for the years between the last two censuses are revised as intercensal estimates.  When the 2006 postcensal estimates were released, Statistics Canada also released revised intercensal CSD estimates for 1996-2005.  The IntelliHealth population estimates were updated from 1996 with the revised population estimates. 
  • Recording the date of extraction of population data from IntelliHealth is recommended because of the revisions that are made with new releases of population estimates.
  • Population estimates do not take into account transient populations, such as post-secondary students or the homeless.
  • Local population estimates may be available (e.g., public health unit level, municipal level) which use different methods or data sources than those used by Statistics Canada and/or the Ministry of Finance which have been described here.
  • The LHIN population data in Intellihealth are provided by two sources, Statistics Canada (estimates up to 2000) and the Ontario Ministry of Finance (estimates beginning with 2001 and all years for projections).The only levels of geography available in the LHIN population data sources are province and LHIN. Statistics Canada (STC) calculated population estimates for LHIN areas starting from intercensal population estimates for census divisions (CD) estimates. STC applied conversion factors derived from the 2001 and 2006 census population counts to determine the proportion of a CD that fell within a LHIN where CDs are split between LHINs. Statistics Canada assumed that the sub−area’s share of the CD population remained constant over time. 
  • The LHIN estimates for 1986-2000 are based on CD estimates that were revised after the 2001 and 2006 censuses.  The CSD estimates for 1986-1995 were not revised to reflect CD revisions.  Therefore Ontario totals from the PHU/county/municipality table and the LHIN table in IntelliHealth will be slightly different for 1986-1995.
  • At the request of the Ministry of Health and Long−Term Care, the Ministry of Finance (MoF) developed a methodology to create projections for LHINs. The MoF methodology for allocating populations to LHINs is more detailed than the STC methodology, and differs depending on LHIN location and the geographic composition of the LHIN. Ministry of Finance used their projections methodology to reallocate the STC census sub−division (CSD) estimates to LHINs for 2001 onwards. Only the MoF estimates for LHINs are provided in Intellihealth beginning in 2001 
  • LHIN population estimates are updated by Ministry of Finance each year when CSD estimates are released.  LHIN estimates for previous years are also revised to reflect CSD revisions released for previous years.  MoF also provides a methodology document2 each year that is available from the MOHLTC.

References and Resources

  1. Gilbert S, Statistics Canada, Demography Division.  Methodology, Postcensal estimates of census subdivisions –  population by age and sex. April 2010
  2. Ontario Population Estimates: Highlights. PHERO, Vol. 3, No. 5, pp. 72-73, March 13, 1992
  3. Bender R. Impact of New Population Estimates on Health and Vital Statistics, Health Reports 1995;7(1):7-18
  4. Bains N, Ranger R. A comparison of Population Estimates and Population Projections for Eastern Ontario. Health Information Partnership Eastern Ontario Region, 2001.

Changes Made 

DateType of Review (Formal Review or Ad Hoc?)Changes made by         Changes
August 2010 Formal reviewSocial Determinants of Health sub-group
  • Citations updated
  • Data notes updated


Lead Author(s)
Nancy Ramuscak, Region of Peel Public Health
Cam McDermaid, Ottawa Public Health
Luanne Jamieson, Hamilton Public Health Services
Virginia McFarland, Grey Bruce Public Health
Alissa Palangio, Sudbury and District Health Unit
William Kou, York Region Community and Health Services

Contributing Author(s)
Core Indicator Reviewers
External Reviewers
Carol Paul, Ministry of Health and Long-Term Care
Jessica Deming, Region of Waterloo Public Health
Mike Delorme, Region of Waterloo Public Health

This page last updated: April 8, 2011
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