A method you can check
Each signal is a local historical measurement, tied to an issuing authority and a defined observation window.
We start with public permit records, preserve the original source, normalize trade names and reconstruct a project only when the linkage method can be explained and tested.
Collect
We use permit records published by the issuing authority. Source records remain separate from derived data.
Resolve
Permits are joined into a physical project through a documented procedure, not an assumed field name.
Measure
At a moment in a timeline, we calculate how often a target trade appears within a stated horizon.
Publish
We show the market, sample size and time window. Data unavailable at that moment is never used.
Why every market is separate
Permit systems, trade labels and project timing vary by issuing authority. A result that works in Philadelphia is evidence for Philadelphia — not a national accuracy claim.
Source and freshness
Page footers name the update date. Figures are derived from public records and should be checked against the issuing authority before any commercial decision.