Data releases

Changelog

Every dataset version since first publication, including versions that predate frozen files.

1. 2026-09-16Method v3

   Location basis for every mega project, re-researched site coordinates where a public source identifies the campus, and the first derived spatial facts: distance from each site-located project to the nearest 230 kV or higher transmission line.

   • Added location_basis to the mega project exports: site (campus footprint identified), address (public address, geocoded), city-centroid, or county-centroid. The JSON export also carries locationSource where the location comes from a different public source than the figures.
   • Re-researched campus coordinates. Projects upgraded to site or address carry a new coordinate and a dated location source; centroid projects keep their previous coordinate.
   • Added transmission proximity, derived in PostGIS from the HIFLD Electric Power Transmission Lines layer (data current to 2023-09-05) filtered to 230 kV and above: nearest line distance, voltage, and owner per project, and the count of site-located projects within 5 miles. The derived values live in derived-facts.json with their own measurement date and are not part of the frozen exports in this release.
   • Only site- and address-located projects count toward any distance fact; centroid coordinates can sit several miles from the parcel, so the prose states the site-located denominator and excludes the rest.
   • Methodology version 3.

2. 2026-09-14Method v2

   Full OSM facility refresh, every mega project re-researched against a dated public source, per-figure basis and confidence columns, and state estimates reconciled to the national count.

   • Refreshed the OpenStreetMap facility layer through the Overpass API and reassigned every facility to a jurisdiction by point-in-polygon against Census boundaries.
   • Re-researched all tracked mega projects. Each now carries a public capacity figure, a public investment figure, a source (label, URL, date), a capacity basis, an investment basis, and a confidence rating. Projects with no public figure for either were retired rather than estimated.
   • Added the columns capacity_basis, investment_basis, is_estimate, confidence, included_in_aggregate, comparable_campus_investment, source_label, source_url, source_date, last_verified_at, and url to the mega project exports.
   • State estimates now reconcile to the Baxtel national count exactly (methodology version 2). This derivation landed on 2026-09-15, after the data refresh date, so estimated_total values in this release differ from the site as served on 2026-09-14 while osm_verified values do not.
   • Coverage is 46 states, the District of Columbia, and Puerto Rico.
   • First frozen release. Earlier versions were served only at the moving URLs and cannot be reproduced byte for byte.

3. 2026-03-11Method v1 · no frozen files

   Last data change before the 2026-09-14 refresh, as recorded in DATASET_UPDATED at the time. Not itemized.

4. 2026-03-09Method v1 · no frozen files

   First publication of the US Data Center Directory.

Methodology versions

The method version changes when the way a number is derived changes, independent of the data refresh date. Compare it before comparing estimates across releases.

Version 3since 2026-09-16

Every mega project carries a location basis (site, address, city centroid, or county centroid). Transmission proximity is derived as the geodesic distance from each project coordinate to the nearest HIFLD transmission line of 230 kV or higher, computed in PostGIS on geography and committed as JSON at refresh time; only site- and address-located projects count toward the within-5-miles fact, and every derived sentence names the layer vintage and its denominator.

Version 2since 2026-09-15

State estimates reconcile to the Baxtel national count exactly: Baxtel state counts where published, the remainder allocated in proportion to OSM-verified count with a derived multiplier (largest-remainder rounding). Every mega project carries a capacity basis, an investment basis, a confidence rating, and a dated public source.

Version 1since 2026-03-09

State estimates were OSM-verified counts times a fixed multiplier (2.9 at the last version 1 refresh). Mega project figures were compiled without a per-figure basis or confidence rating.

Full method, reconciliation table, and investment split on the hub methodology block.