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RE413

Behind the Data

Data Refresh Log

Every figure on this site carries a source and a date. This is the same claim in aggregate: when the data last landed, what moved, and what has to pass before anything is published.

Sources Last Checked
August 5, 2026
when we last asked for new figures
Subjects Tracked
5
across all 101 towns
Records Reach Back To
1960
the oldest continuous series here

How the Refresh Works

A scheduled job checks the source publications on a tiered schedule, matched to how often each subject actually moves. Rates and fuel prices are republished weekly. Assessor rolls and census tables move once a year, and checking those every week would be pointless load on a public service.

Nothing lands unless it passes. Each run rebuilds every derived figure and then runs the full test suite against the fresh data. If a figure regressed, a source changed shape, or a town went missing, the run fails and the previous data stays up. Data is committed only because the checks went green.

"Changed" means the figures moved. Every pull is stamped with the date it ran, so counting that as a change would mark everything as updated every week. We compare the content itself, which is why a run can honestly report that we checked and the publishing bodies had put out nothing new.

Checked is not the same as current. This page tells you when we last asked the publishing bodies for new figures. It cannot tell you how old their figures are, and those are different things: a census table published in 2023 and a tax rate set for fiscal 2026 are both "checked today" and neither is from today. The period a figure actually covers is stated beside that figure, on the page it appears on, because that is where it means something.

We publish what we hold and who published it. We do not publish the machine addresses, query parameters or per-source schedules behind each pull: naming the publishing body is the attribution these public sources ask for, and the assembly is our own work.

What the Data Runs Through

Every dated series we publish and the period its figures cover, straight from each publisher's own release. "Checked" in the chrome is when we last asked; this is what the answers actually contain. A further 25 sources are living registers (facility lists, service areas, schedules) that are current as of our last check, and 5 are one-time surveys that do not update.

Every dated series and the period its figures run through.
SeriesFigures Run ThroughPublisher
Affordability Gap Analysis (HUD)2018–2022 survey windowU.S. Department of Housing and Urban Development
Annual Population Estimatesestimates through 2024U.S. Census Bureau
Assessed Values and ParcelsFY2027 (assessment years vary by town, FY2019–FY2027)MassGIS, Massachusetts Bureau of Geographic Information
Building Permits, Town by Town1980–2025U.S. Census Bureau
Business Counts by ZIP2023U.S. Census Bureau
Census Geography Crosswalk2023 GazetteerU.S. Census Bureau
Census Population Counts2020 censusU.S. Census Bureau
Climate Normals1991–2020 normalsNOAA National Centers for Environmental Information
Community Resilience Estimates2024U.S. Census Bureau
Commutes, Education and Housing Age (Census Survey)2019–2023 survey windowU.S. Census Bureau
County Employment and Wages2024U.S. Bureau of Labor Statistics
County House Price Index2025Federal Housing Finance Agency
County Unemployment2026U.S. Bureau of Labor Statistics
Decennial Census Housing Counts2020 censusU.S. Census Bureau
Elevation Survey Flights2013–2021 flightsMassGIS, Massachusetts Bureau of Geographic Information
Environmental Justice Populations2020MassGIS, Massachusetts Bureau of Geographic Information
Fuel and Electricity Prices2026-05U.S. Bureau of Economic Analysis
Heating Fuels and Housing Stock (Census Survey)2020–2024 survey windowU.S. Census Bureau
Housing Cost Burden (Census Survey)2019–2023 survey windowU.S. Census Bureau
HUD Rent StandardsFY2026U.S. Environmental Protection Agency
Income and Work (Census Survey)2020–2024 survey windowU.S. Census Bureau
Income, Value and Rent Series (Census Survey)2009–2023 vintagesU.S. Census Bureau
Land Use Snapshots1971, 1985 and 1999 snapshotsMassGIS, Massachusetts Bureau of Geographic Information
Local Lender Rate Survey2026-08-05U.S. Department of Housing and Urban Development
Migration Flows (Census Survey)2018–2022 survey windowU.S. Census Bureau
Mortgage Rate History2026-07-30Freddie Mac
Natural Hazard Risk Index (County)December 2025 releaseFederal Emergency Management Agency
Natural Hazard Risk Index (Tract)December 2025 releaseFederal Emergency Management Agency
New Homes Permitted2025U.S. Census Bureau
Per-Pupil School SpendingFY2024U.S. Environmental Protection Agency
Reported Chemical Releases (TRI)2024U.S. Environmental Protection Agency
State Aid to Towns (Cherry Sheets)FY2027 estimatesU.S. Environmental Protection Agency
Subsidized Housing Inventory (40B)September 30, 2025Massachusetts Executive Office of Housing and Livable Communities
Tax Rates and Town FinancesFY2026 certificationsU.S. Environmental Protection Agency
The Town Records (Derived)per component seriesMultiple bodies
This Week's Mortgage Rate2026-07-30Freddie Mac
Town Boundaries2020 census boundariesMassGIS, Massachusetts Bureau of Geographic Information
Town Land Areas2024U.S. Census Bureau
Traffic Counts2024 inventoryMassachusetts Department of Transportation
Walkability Index2021 Smart Location DatabaseU.S. Environmental Protection Agency
Water Quality Assessments2022 Integrated ListMassachusetts Department of Environmental Protection
Where People Work (Commute Census)2022U.S. Census Bureau
Who Moved In and Out (IRS)2021–2022 filing yearsInternal Revenue Service

What Each Subject Covers

The subjects that appear in the history below, and the bodies behind each.

Property and Housing

Assessed values, tax rates, the housing stock, and what has sold.

Massachusetts Department of Elementary and Secondary Education · Massachusetts Department of Environmental Protection · Massachusetts Executive Office of Housing and Livable Communities · Massachusetts Historical Commission · MassGIS, Massachusetts Bureau of Geographic Information · U.S. Census Bureau · U.S. Environmental Protection Agency · U.S. Geological Survey

Newest figures cover through FY2027 (assessment years vary by town, FY2019–FY2027). 3 sources are living registers, current at our last check.

Work and Income

Employment, wages, commuting patterns and the local economy.

Internal Revenue Service · U.S. Bureau of Economic Analysis · U.S. Bureau of Labor Statistics · U.S. Census Bureau

Newest figures cover through 2026.

Hazards and Environment

Flood mapping, wetlands, contaminated sites, dams and reported releases.

Federal Emergency Management Agency · Massachusetts Department of Conservation and Recreation · Massachusetts Department of Environmental Protection · NOAA National Centers for Environmental Information · U.S. Census Bureau · U.S. Environmental Protection Agency

Newest figures cover through December 2025 release. 8 sources are living registers, current at our last check.

Utilities and Infrastructure

Water and sewer service, gas, electricity, broadband, roads and transit.

Massachusetts Department of Environmental Protection · Massachusetts Department of Transportation · MassGIS, Massachusetts Bureau of Geographic Information · The regional transit authorities · U.S. Environmental Protection Agency · U.S. Geological Survey

Newest figures cover through 2024 inventory. 11 sources are living registers, current at our last check.

Rates and Prices

Mortgage rates, fuel prices and the national series behind local costs.

Community Preservation Coalition · Federal Housing Finance Agency · Freddie Mac · Massachusetts Executive Office of Housing and Livable Communities · MassGIS, Massachusetts Bureau of Geographic Information · U.S. Census Bureau · U.S. Department of Housing and Urban Development · U.S. Environmental Protection Agency

Newest figures cover through FY2027 estimates. 3 sources are living registers, current at our last check.

How Far Back the Record Goes

Refreshing brings the newest figures in. The archive underneath them is decades deep, because the agencies behind these series have been publishing them for decades and we hold the whole run, not just the latest reading.

Mortgage Rates
Since 1971
664 monthly observations
Cost of Heat
Since 1990
795 weekly readings
Homes Permitted
Since 1980
46 years, all 101 towns
Population
Since 1960
7 census counts

Refresh History

Newest first, and it grows from here: this log records each run as it happens rather than reconstructing what came before it. Runs that changed nothing are listed too, because knowing we checked on a given date and the publishing bodies had put out nothing new is the point of keeping it.

August 5, 2026

seednew figures published

  • Hazards and Environment
  • Property and Housing
  • Rates and Prices
  • Utilities and Infrastructure
  • Work and Income

If a Figure Looks Wrong

Public records contain errors, and we copy them faithfully. If a figure here disagrees with the town's own records, the town is right and we want to know. The contact is on the about page.

A recent refresh date means the figures were checked recently. It is not a warranty that they are accurate, current or complete. See the terms of use.