A Beginner's Guide to Reading City Data: Census, BLS, and What Our Index Actually Combines
Published July 17, 2026
Almost every credible city statistic you'll see online - on this site or elsewhere - traces back to one of two federal sources: the US Census Bureau or the Bureau of Labor Statistics. Knowing what each one actually measures makes you a much more critical reader of any "best places to live" article, including ours.
The US Census Bureau: population, income, housing, education
Most of what appears on our demographics pages - population, median household income, home values, rent, education levels, commuting patterns, housing tenure - comes from the Census Bureau's American Community Survey (ACS), specifically the 5-year estimates. "5-year estimates" means the figures are a rolling average built from five years of survey responses, not a single point-in-time count. That's a deliberate trade-off: it makes the numbers far more statistically reliable for small and mid-sized cities, at the cost of being slightly less current than a single-year snapshot - a real change happening today might take a couple of years to fully show up.
The Bureau of Labor Statistics: wages and employment
Our employment pages - median annual wage, unemployment rate, labor force size - come from the BLS's Occupational Employment and Wage Statistics (OEWS) program. This is survey data collected directly from employers, published with roughly a one-year lag, and it's the same authoritative source labor economists and compensation analysts use professionally - not a crowdsourced or self-reported figure.
What our index adds on top of the raw data
The raw Census and BLS numbers don't come pre-packaged as a single "cost of living score." Our cost of living index combines them into a weighted composite (housing weighted most heavily, then transportation and food, then utilities and healthcare) anchored to 100 = US national average - see our full explanation of how the index is built for the exact methodology and weights.
Questions worth asking about any city statistic you read online
- Is the source named? If an article cites a number without saying where it came from, treat it as a marketing claim, not data.
- Is it a survey estimate or an actual count? ACS figures are estimates with a margin of error, particularly for smaller cities - a difference of a few percentage points between two similar-sized cities may not be statistically meaningful.
- How old is it? Multi-year survey averages (like ACS 5-year) lag real-time conditions by design; always check the stated year, which we display on every page.
Why this matters for your own decisions
Understanding where the numbers come from doesn't just make you a better reader of our site - it's protection against less careful sources that round wildly, cite no methodology, or blend real government data with guesswork. See our About page for the full detail on our own sourcing and update schedule.