OECD Special Session International Workshop on Defining and Measuring Metropolitan Regions (Paris, France, 27 th November, 2006) Defining an Measuring Metropolitan Areas: A Comparison between Canada and the United States Henry A. Puderer, Chief of Geographic Concepts, Geography Division, Statistics Canada
Presentation Outline Concept comparison Model comparison Focus - criteria and measurement comparison (Canadian examples)
Comparison of the Concept Both countries have the same concept of a metropolitan area. An area containing a large population nucleus and adjacent communities that have a high degree of integration with that nucleus.
Comparison of the Model Both countries have the same, two component, model of a metropolitan area: a core defined using population density (form) a hinterland defined using the relationship between place of residence and place of work (function)
Comparison of the Model (cont d) Metropolitan areas are part of a broader based hierarchy in both Canada and the United States. The structure and scope of these broader hierarchies have similarities and differences.
Comparison of the Model (cont d) Same Metropolitan Statistical Areas and Census Metropolitan areas Micropolitan Statistical Areas and Census Agglomerations Core Based Statistical Areas (CBSA) and C(M)A
Comparison of the Model (cont d) Differences Combined CBSD Metropolitan Regions CBSA Metropolitan Divisions Urban rural continuum U.S. outside CBSD residual Canada Metropolitan Influenced Zones
Comparison of the Model (cont d) Building block county in the United States and the municipality in Canada Counties are larger than municipalities - 2Xs Impact: With smaller building block in Canada generally likelihood for less over or under bounding of metropolitan areas
Criteria and Measurement Each metropolitan area is composed of counties / municipalities (census subdivision CSDs) which respect one or more of the following criteria. 1. Delineation of the nucleus or core 2. Delineation of the hinterland 3. Mergers 4. Delineation of sub-centres within metropolitan areas 5. Consolidations metropolitan regions
Delineation of the Nucleus or Core Delineation of urban areas Urban area population criteria for metropolitan areas Target core delineation
Delineation of urban areas Both use the urban areas as defined by their respective Censuses. Methodologies differ. End results in general are similar: Central core with population density at 400 persons per square kilometer (1000 ppsm) Minimum population required 2500 in the United States and 1000 in Canada Exception: United States form one urban area unless satisfy specific conditions for splitting Canada retain urban area from previous census an auto splitting which recognizes metropolitan area limits
Delineation of urban areas Impact - Toronto urban area could combine with Oshawa and Hamilton to form one urban area and therefore one metropolitan area
Urban area population criteria for metropolitan areas Both countries require urban areas of a minimum size for metropolitan areas. United States urban area (urbanized area) of at least 50,000 Canada total CA population of at least 100,000 with at least 50,000 resident in the urban core Impact: For 2006 Census, American threshold would classify 16 CAs as CMAs (increase from 33 to 49)
Target core delineation Need target core for commuting calculations Define by including whole counties or municipalities to the target core: United States: at least 50% of county population or at least 5000 persons are resident with urbanized area - forms central county (or counties) Canada: a municipality becomes part of the target core if 75% of the CSD population is in the urban area Impact on metropolitan delineation: Affect of urban area delineation differences are dampened, impact is on timing of community entry because of population thresholds and building block differences
Delineation of the hinterland Commuting data forward and reverse commuting Commuting thresholds
Commuting data forward and reverse commuting Use place of work and place of residence data (commuting data) to delineate the hinterland Forward commuting commuting from an outlying community to the target core Reverse commuting commuting from the target core to outlying community Impact: No difference
Commuting thresholds United States: Forward commuting - at least 25% of the employed residents of the county work in the central county (counties) Reverse commuting at least 25% of the employment in the county is accounted for by workers residing in the central county (counties) of the metropolitan area Canada: Forward commuting at least 50% Reverse commuting at least 25%
Commuting thresholds (cont d) Forward commuting: Absolute forward commuting threshold differences reflect differences in geographic building block National out-commuting averages Equivalent Reverse commuting Absolute reverse commuting threshold are the same despite differences in building blocks Equivalent?
Commuting thresholds (cont d) Impact: Little impact more-or-less equivalent attempts at calibration
Mergers Merger criteria differ United States: Two adjacent CBSAs are merged if central county (counties) of one CBSA meet the commuting requirements to the central county (counties) of the other CBSA Canada: No CMA to CMA mergers only CA to CMA mergers Total forward commuting interchange is equal to 35% of the resident employed labour force of the CA
Mergers (cont d) Impact: Where mergers are permitted Canadian criteria require less commuting exchange In the case of Toronto CMA none of the peripheral CAs would merge when applying the US criteria (over 225,000 people or almost 5% of the total 2001 CMA population)
Delineation of sub-centres within metropolitan areas United States: procedures to delineate metropolitan divisions No equivalent procedure in Canada Impact: Application of American methodology to the Toronto CMA would identify the municipality of Mississauga as a metropolitan division Perhaps 4 other CMAs could be considered
Consolidations metropolitan regions United States: procedures to consolidate (combine) CBSAs Combine if employment interchange is 25% or more (% of forward commuting from smaller CBSA to larger plus % reverse commuting from larger CBSA to smaller) Combine if supported locally when employment interchange is from 15% to less than 25%. Canada: no directly equivalent procedure in Canada. Is partly reflected in the merger criteria but only applies to combining CAs with CMAs. No CMA with CMA consolidation.
Consolidations metropolitan regions Impact: Toronto as the test case Oshawa at 60% employment interchange would be combined (2001-296,298 ) Hamilton at 20% employment interchange could be combined depending on local input (2001 662,401) Potential increase of 958, 669 or 20% All peripheral CAs would be combined with Toronto under this criteria
Summary Differences National level and metropolitan specific comparisons Urban areas Same number Same start point Comparable Urban area limits Canada retains historic limits - splits relative to CMAs US would create one urban area Potential for an impact in Canada for individual CMAs Toronto area Thresholds different Effects national comparability but can be adjusted
Summary (cont d) Target core Same process different thresholds Dampens urban area limit differences - more a question of when Little impact at national level but could impact individual metropolitan area comparisons Commuting data and thresholds Same data Same approach to calibrating thresholds Equivalent
Summary (cont d) Geographic building block Different smaller in Canada more precise delineations less over or under bounding US building block delineates larger metropolitan areas In 1990 in collaboration with Richard L. Forstall of the U.S. Census Bureau exchanged and applied methodologies in US over bounding 9 to 35% and under bounding 10 to 20% Methodology in United States has changed
Summary (cont d) Cumulative impact needs testing Canada / USA Comparison, slide from presentation by Marc J. Perry, Population Division, U.S. Census Bureau, presentation at the Annual Meeting of the Association of American Geographers, Chicago, Illinois, March 11 2006) 70% / 83%
Canada / USA Comparison
Summary (cont d) Cumulative impact needs testing MIZ strong 5%, moderate 8% Real settlement difference or methodology difference?
Summary (cont d) Mergers An impact on national and individual metropolitan area comparability 11 of 33 CMAs in Canada are impacted Reduce CMA population by about 700,000 or 4%
Summary (cont d) Sub-centres No comparable criteria in Canada No impact at national level or individual metropolitan area Does conceal metropolitan area complexity and makes intra-metro comparisons more difficult but limited (2 to 4 ) CMAs
Summary (cont d) Combining metropolitan areas CAs not included in CMAs in Canada using the US merger criteria could be combined to form metropolitan regions when applying US criteria for combining CBSAs Need to apply consolidation criteria between CMAs as well to create comparable metropolitan regions
Best Comparisons Three categories of best comparisons re CMAs to metropolitan statistical areas Group 1: direct one to one comparisons (20 CMAs) Group 2: CMA to combined statistical area (8 CMAs) CA mergers are included in the CMA, no issues with adjacent CMAs Some CAs could merger with CMAs based on US criteria but more likely not all (if all then these CMAs would be in group 1) Group 3: CMA is not comparable (5 CMAs) CA mergers present but CMA to CMA combinations are not included Caught somewhere in between Group 1 and 2 Shaded CMAs could become part of metropolitan region under combination (consolidation) criteria (5 CMAs also in group 1)
Group 1 Group 2 Group 3 Greater Sudbury Calgary Abbotsford Halifax Edmonton Barrie Kelowna London Brantford Kingston Montreal Guelph Moncton Ottawa-Gatineau Kitchener Peterborough Saguenay Hamilton Quebec St. John's Oshawa Regina W indsor St. Catharines-Niagara Saint John Toronto Saskatoon Vancouver Sherbrooke Thunder Bay Trois-Rivieres Victoria W innipeg