The OMB defines a core-based statistical area (commonly referred to as a CBSA) as the county or counties (or county-equivalents) surrounding at least one densely-settled core of at least 10,000 population,[2] "plus adjacent counties having a high degree of social and economic integration with the core as measured through commuting ties with the counties containing the core".[2] The OMB further divides core-based statistical areas based on population into metropolitan statistical areas (MSAs) for those with at least 50,000 and micropolitan statistical areas (μSAs) for those with 10,000 to 49,999 people.[2]
Primary statistical areas (PSAs) include all combined statistical areas and any core-based statistical area that is not a constituent of a combined statistical area. Of the 12 statistical areas of Massachusetts, five are PSAs comprising two combined statistical areas, one metropolitan statistical area and two micropolitan statistical areas.
The five primary statistical areas of the Commonwealth of Massachusetts[b]
^An out-of-state area and its population are displayed in green.An area that extends into more than one state is displayed in purple. A purple population number over a black population number show the total population versus the in-state population. The state's abbreviation is also shown next to the in-state total.
^For PSAs comprising populations from multiple states, they are listed twice to show both their intrastate population within that PSA as well as the PSA's total population. Only the intrastate population is ranked.
^ abcdeRevised Delineations of Metropolitan Statistical Areas, Micropolitan Statistical Areas, and Combined Statistical Areas, and Guidance on Uses of the Delineations of These Areas (July 21, 2023). "0MB BULLETIN NO. 23-01"(PDF). Office of Management and Budget. Retrieved October 23, 2023.{{cite web}}: CS1 maint: multiple names: authors list (link)