 SCORECARD ARENAS DISCOVERY FOUNDATIONS FOR AGENTS 

← HOUSING / US VINTAGE 2339d9eb PENDING

East North Central · 12M

On 4 August 2026 we predicted East North Central house prices would be 3.23% higher by May 2027.

Our stated range was 373.702 to 411.901 — if the method works as intended, the true figure lands inside it about 95% of the time. Verdict due the first FHFA release covering May 2027, when the official figure is published. It has not been graded yet, and nothing on this page can change what was written above.

01 / WHAT WAS LOCKED

FORECAST · INDEX LEVEL 392.337

CHANGE FROM BASE +3.23%

95% INTERVAL 373.702 … 411.901

 BASE — LAST FIGURE PUBLISHED BEFORE THE LOCK 380.070 · 2026-05-01 

 TARGET PERIOD 2027-05-01 

 LOCKED AT — TIMESTAMP ASSIGNED BY THE DATABASE 2026-08-04T22:05:03.879228+00:00 

02 / WHEN THIS GETS ITS VERDICT

This forecast is graded against the FIRST figure the publisher releases for May 2027 — the number the market actually saw — and never against a later revision. That rule was fixed on 2026-08-03, before this forecast existed.

Headline grade (first_print): the earliest publisher vintage at or after the target period. Available roughly two months after the period ends, on the publisher's schedule, not ours.

Companion grade (settled_t_plus_12): the value as published twelve months after the target period, which measures how much the first figure was revised. Available roughly fourteen months after. Both definitions were committed before any grade existed under either.

INSUFFICIENT DATA

This forecast has not been graded. It cannot be: the period it names has not been published yet. When it is, the verdict appears here — pass or miss — and nothing on this page changes.

03 / PROVENANCE

 VINTAGE ID 2339d9eb-d601-44d6-95c1-61bd0b634722 

 ARENA housing_us 

 SERIES EAST_NORTH_CENTRAL 

 TARGET PERIOD 2027-05-01 

 LOCKED AT 2026-08-04T22:05:03.879228+00:00 

 MODEL ar12_logdiff 

 MODEL SPEC 1.1 

 MODEL SELECTION 425 observations >= 60 

 POINT STATISTIC median 

 FIT WINDOW 425 observations, 1991-01-01 → 2026-05-01 

 ARCHIVE AS OF 2026-08-04 

 COMMIT SHA 63e0fa12edfd75bea8ff26683a080669bd5c9473 

 RUN MANIFEST 9d992102-c049-4495-9a2f-1cfe4ca48d68 

PUBLISHER VINTAGES THIS FORECAST WAS BUILT FROM

Every input the reconstruction used, with the time the publisher released it. The forward-lock check reads these back from the record and fails the run if any of them postdates the lock above — that is what makes "locked before the outcome existed" a checked statement rather than a claim.

INPUT	PUBLISHER RELEASE TIME
observations:EAST_NORTH_CENTRAL@2026-08-04	2026-08-04T00:00:00Z

CONTENT DIGEST

d3343841ab895872a5e52577df606a93cf6cccf670c55b944fb81c036f350ffe

SHA-256 over the payload serialized with object keys sorted lexicographically at every depth and no whitespace, computed when this page was built. It is not stored on the row, and it is not the commitment: the commitment is the append-only row and the lock timestamp the database assigned to it. Fetch the same payload from /v1/vintages and repeat this to check it.

04 / THE LOCKED PAYLOAD, VERBATIM

{
  "as_of": "2026-08-04",
  "model": "ar12_logdiff",
  "interval": {
    "label": "95%",
    "lower": 373.70177163623987,
    "upper": 411.90136967374764,
    "method": "ma_representation",
    "log_variance": 0.0006164533714088406
  },
  "base_value": 380.07,
  "commit_sha": "63e0fa12edfd75bea8ff26683a080669bd5c9473",
  "fit_window": {
    "last_period": "2026-05-01",
    "first_period": "1991-01-01",
    "observations": 425
  },
  "base_period": "2026-05-01",
  "forecast_value": 392.3369363015331,
  "horizon_months": 12,
  "forecast_inputs": [
    {
      "ref": "observations:EAST_NORTH_CENTRAL@2026-08-04",
      "as_of": "2026-08-04T00:00:00Z"
    }
  ],
  "point_statistic": "median",
  "run_manifest_id": "9d992102-c049-4495-9a2f-1cfe4ca48d68",
  "model_spec_version": "1.1",
  "model_selection_reason": "425 observations >= 60"
}

GET /v1/vintages/2339d9eb-d601-44d6-95c1-61bd0b634722

The One Lab · Toronto · Every number on this site resolves to a primary source or a graded model output. Where it can't, we say so. VINTAGE 2339d9eb · WRITE-ONCE · NOT YET GRADED