thesisPrototype

Conditional

2027 child SPM poverty rate if ACTC threshold falls to $1

What will the U.S. Census Bureau first print for the CY2027 Supplemental Poverty Measure percentage of children under age 18 below poverty, ALL RACES, using the revised SPM methodology, with seasonal adjustment not applicable, conditional on the specified IRC §24 earned-income-threshold legislation?

Conditional on: For the CY2027 Census Supplemental Poverty Measure child-poverty outcome, legislation enacted by 2027-12-31 makes the IRC §24(d)(1)(B)(i) earned-income threshold no more than $1 for tax year 2027.

Forecast

13.2%
6.8%–19.6%
80% prediction interval
gpt-5.6-solRun record ↗

Cumulative probability

Chance that the outcome is at or below each value.

0%25%50%75%100%-2.8%13.2%29.2%Forecast value

Shaded band: 80% interval (6.8%–19.6%). Dashed line: point estimate (13.2%).

Derived from the point estimate and 80% interval; the agent did not report a full distribution.

Analysis

§CY2027 Census child Supplemental Poverty Measure conditional forecast

Framing: the target is the first revised-methodology Census annual print for CY2027, Table B-2, ALL RACES, Under 18 years / Below Poverty / Percent. This annual household measure is not seasonally adjusted. The registered 2028-12-31 resolutionDate is a Thesis resolve-by bound, not a claimed release day.

▸ Reported tool use: thesis_announcement_fetch.fetch_official_announcementmodel report
fetch_official_announcement({"url":"https://www.census.gov/newsroom/press-releases/2026/statement-on-supplemental-poverty-measure.html"})
↳ Exact registered URL returned HTTP 200, 326626 response bytes, SHA-256 96df23435b2c06235539b01f1069fe6959df3d4aa808bd1432aa5c6856a28cd4. The Census page is dated 2026-07-17 and announces plans to re-release 2019–2024 SPM estimates; it authenticates methodology identity, not the Thesis release window or deadline.
▸ Reported tool use: census.table_b2.fetchmodel report
Fetch and parse https://www2.census.gov/programs-surveys/demo/tables/p60/287/tableB-2.xlsx at ALL RACES / Under 18 years / Below Poverty / Percent using the repository resolver parser.
↳ Fetched 43484 bytes, SHA-256 8cdb688380c543c1bd3bc47e2124ec6872511eff8c03c8340b1adacdbd1525fe. Current-method P60-287 Table B-2 values are 2019 12.6%, 2020 9.7%, 2021 5.2%, 2022 12.4%, 2023 13.7%, and 2024 13.4%; every parser check returned error=None.
▸ Reported tool use: thesis.model_candidatesmodel report
Generate thesis_model_candidate_v1 persistence candidate from fetched 2019–2024 values.
↳ {"schemaVersion":"thesis_model_candidate_v1","model":"persistence","point":13.4,"p10":7.6,"p50":13.4,"p90":19.2,"ci80":[7.6,19.2],"ci90":[5.9,20.9],"intervalMethod":"empirical successive-change normal approximation","calibration_n":5,"trainCutoff":"2024","walkForwardScore":{"metric":"MAE","value":3.24}}. Fetched-history changes were -2.9, -4.5, +7.2, +1.3, and -0.3 percentage points.
▸ Reported tool use: policyengine.economymodel report
POST threshold-zero reform to PolicyEngine, inspect reform policy 85587 versus current-law policy 2, request /us/economy/85587/over/2?region=us&time_period=2027, and inspect the public Thesis PolicyEngine artifact.
↳ PolicyEngine API policy 85587 sets gov.irs.credits.ctc.refundable.phase_in.threshold to 0 from 2026 onward, an economic approximation to statutory $1; baseline policy 2 is labeled Current law. The live 2027 economy request returned status=computing, so it supplies no finished 2027 estimate and increases uncertainty. The public 2026 model artifact (policyengine-us 1.764.6) reports child poverty 0.1701733 baseline versus 0.1682073 reform: change -0.001966, or -0.1966 percentage points; budgetary impact was -$1.8261 billion.
▸ Reported tool use: congress.bill_textmodel report
Fetch official enrolled-format XML for introduced S.3596 from Congress.gov and inspect Section 2.
↳ The 2928-byte official bill XML says §24(d)(1)(B)(i) changes $3,000 to $1, strikes §24(h)(6), and applies after 2025-12-31. With the 15% phase-in unchanged, moving the operative threshold from $2,500 to $1 raises a phase-in-limited family's potential refundable credit by at most about 0.15 × $2,499 = $374.85 before caps and take-up.

Base rate/reference class: the admissible current-method 2019–2024 Census first-print vector is 12.6%, 9.7%, 5.2%, 12.4%, 13.7%, and 13.4%; mean 11.17%, range 5.2%–13.7%. No official revised-methodology print or backcast was available, so the current-method vintage is used without fabricating a revision. The strongest benchmark is 2024 last-print persistence at 13.4%; the policy update is small relative to the historical dispersion.

Prior/update/interval: persistence prior = 13.4%. PolicyEngine's direct model input gives -0.1966pp, rounded to a -0.2pp directional inside-view update; because the live 2027 economy run was unfinished, it is not treated as a completed 2027 estimate. No separate momentum or macro update is supported, so point = 13.4 - 0.2 = 13.2%. From fetched successive changes [-2.9, -4.5, 7.2, 1.3, -0.3], sample sigma = 4.5319pp. The nominal 80% half-width is 1.28*sigma = 1.28 × 4.5319 = 5.8008pp. Widen by 1.10 for the announced revised-methodology transition, the unfinished live 2027 PolicyEngine run, and the limitation of calibrating volatility from only five annual changes: 5.8008 × 1.10 = 6.3809pp. Thus 13.2 ± 6.3809 = [6.8191, 19.5809], published as [6.8, 19.6]. Four of the five observed annual moves—80%—fit within ±6.3809pp.

Mechanism and counter-consideration: the condition reaches very-low-earning families by starting the ACTC phase-in near the first dollar, but the unchanged 15% rate limits the mechanical gain to roughly $375 and nonfiling can prevent take-up. The modeled -0.2pp effect is therefore applied once, not double-counted with the 2021 expanded-CTC observation. Upside risk would land above the interval if the revised SPM methodology sharply raises measured child poverty while a recession substantially reduces low-income earnings. Downside risk would land below the interval if unexpectedly strong earnings combine with much broader refundable-credit legislation or unusually complete filing take-up.

Review disposition: accepted both optional suggestions by clarifying that the -0.2pp PolicyEngine adjustment is a directional inside-view input rather than a completed 2027 estimate and by identifying the five-change volatility sample as an interval-calibration limitation. No required fixes were identified.

Key drivers

  • 2024 last-print persistence prior
  • ACTC phase-in beginning near the first earned dollar
  • Limited maximum gain of about $375 per phase-in-limited family
  • Low-income nonfiler take-up
  • Revised-SPM methodology transition

Tool evidence

This run has no captured tool responses. “Reported tool use” in the analysis is the model’s account, not an archived tool response.

Sources and resolution

Official source
U.S. Census Bureau revised-SPM methodology announcement (identity) and Poverty in the United States: 2027, Supplemental Poverty Measure Table B-2 (resolving artifact)
Resolution date
December 31, 2028· outcome not recorded
Resolution rule
Resolve to the first Census annual income-and-poverty release artifact for CY2027 using the revised SPM methodology whose identity is authenticated by the registered 2026-07-17 Census announcement: Poverty in the United States: 2027, Supplemental Poverty Measure Table B-2, ALL RACES 2027 row, Under 18 years / Below Poverty / Percent column. The 2028-08-01 through 2028-12-31 expected release window and 2028-12-31 resolve-by deadline are Thesis lab commitments; the announcement does not establish either timing value. Record the published percent without scaling or rounding and ignore later revisions. If the conditioning legislation is not enacted by 2027-12-31, mark this conditional unresolved.
Run details

The analysis is the model’s written report. Tool-use descriptions in that report are model claims; the activity artifacts contain the execution record.

thesis.analyst · gpt-5.6-sol · full · v2.5.7

pre-submit review · completed

Draft is publication-ready on the review rubric, with resolver fields, base-rate prior, update logic, interval method, tails, and JSON fields coherent with the registered target.

  • info optional_suggestion: Consider stating explicitly that the -0.2pp PolicyEngine adjustment is used only as a directional inside-view input because the live 2027 economy run was unfinished.
  • info optional_suggestion: Consider noting that the small 2019-2024 volatility sample is a limitation even though the widened interval partly accounts for the methodology transition.

disposition not applicable: Review disposition: accepted both optional suggestions by clarifying that the -0.2pp PolicyEngine adjustment is a directional inside-view input rather than a completed 2027 estimate and by identifying the five-change volatility sample as an interval-calibration limitation. No required fixes were identified.

disposition not applicable: Review disposition: accepted both optional suggestions by clarifying that the -0.2pp PolicyEngine adjustment is a directional inside-view input rather than a completed 2027 estimate and by identifying the five-change volatility sample as an interval-calibration limitation. No required fixes were identified.

Activity artifacts

Complete original trace

§CY2027 Census child Supplemental Poverty Measure conditional forecast

Framing: the target is the first revised-methodology Census annual print for CY2027, Table B-2, ALL RACES, Under 18 years / Below Poverty / Percent. This annual household measure is not seasonally adjusted. The registered 2028-12-31 resolutionDate is a Thesis resolve-by bound, not a claimed release day.

▸ Reported tool use: thesis_announcement_fetch.fetch_official_announcementmodel report
fetch_official_announcement({"url":"https://www.census.gov/newsroom/press-releases/2026/statement-on-supplemental-poverty-measure.html"})
↳ Exact registered URL returned HTTP 200, 326626 response bytes, SHA-256 96df23435b2c06235539b01f1069fe6959df3d4aa808bd1432aa5c6856a28cd4. The Census page is dated 2026-07-17 and announces plans to re-release 2019–2024 SPM estimates; it authenticates methodology identity, not the Thesis release window or deadline.
▸ Reported tool use: census.table_b2.fetchmodel report
Fetch and parse https://www2.census.gov/programs-surveys/demo/tables/p60/287/tableB-2.xlsx at ALL RACES / Under 18 years / Below Poverty / Percent using the repository resolver parser.
↳ Fetched 43484 bytes, SHA-256 8cdb688380c543c1bd3bc47e2124ec6872511eff8c03c8340b1adacdbd1525fe. Current-method P60-287 Table B-2 values are 2019 12.6%, 2020 9.7%, 2021 5.2%, 2022 12.4%, 2023 13.7%, and 2024 13.4%; every parser check returned error=None.
▸ Reported tool use: thesis.model_candidatesmodel report
Generate thesis_model_candidate_v1 persistence candidate from fetched 2019–2024 values.
↳ {"schemaVersion":"thesis_model_candidate_v1","model":"persistence","point":13.4,"p10":7.6,"p50":13.4,"p90":19.2,"ci80":[7.6,19.2],"ci90":[5.9,20.9],"intervalMethod":"empirical successive-change normal approximation","calibration_n":5,"trainCutoff":"2024","walkForwardScore":{"metric":"MAE","value":3.24}}. Fetched-history changes were -2.9, -4.5, +7.2, +1.3, and -0.3 percentage points.
▸ Reported tool use: policyengine.economymodel report
POST threshold-zero reform to PolicyEngine, inspect reform policy 85587 versus current-law policy 2, request /us/economy/85587/over/2?region=us&time_period=2027, and inspect the public Thesis PolicyEngine artifact.
↳ PolicyEngine API policy 85587 sets gov.irs.credits.ctc.refundable.phase_in.threshold to 0 from 2026 onward, an economic approximation to statutory $1; baseline policy 2 is labeled Current law. The live 2027 economy request returned status=computing, so it supplies no finished 2027 estimate and increases uncertainty. The public 2026 model artifact (policyengine-us 1.764.6) reports child poverty 0.1701733 baseline versus 0.1682073 reform: change -0.001966, or -0.1966 percentage points; budgetary impact was -$1.8261 billion.
▸ Reported tool use: congress.bill_textmodel report
Fetch official enrolled-format XML for introduced S.3596 from Congress.gov and inspect Section 2.
↳ The 2928-byte official bill XML says §24(d)(1)(B)(i) changes $3,000 to $1, strikes §24(h)(6), and applies after 2025-12-31. With the 15% phase-in unchanged, moving the operative threshold from $2,500 to $1 raises a phase-in-limited family's potential refundable credit by at most about 0.15 × $2,499 = $374.85 before caps and take-up.

Base rate/reference class: the admissible current-method 2019–2024 Census first-print vector is 12.6%, 9.7%, 5.2%, 12.4%, 13.7%, and 13.4%; mean 11.17%, range 5.2%–13.7%. No official revised-methodology print or backcast was available, so the current-method vintage is used without fabricating a revision. The strongest benchmark is 2024 last-print persistence at 13.4%; the policy update is small relative to the historical dispersion.

Prior/update/interval: persistence prior = 13.4%. PolicyEngine's direct model input gives -0.1966pp, rounded to a -0.2pp directional inside-view update; because the live 2027 economy run was unfinished, it is not treated as a completed 2027 estimate. No separate momentum or macro update is supported, so point = 13.4 - 0.2 = 13.2%. From fetched successive changes [-2.9, -4.5, 7.2, 1.3, -0.3], sample sigma = 4.5319pp. The nominal 80% half-width is 1.28*sigma = 1.28 × 4.5319 = 5.8008pp. Widen by 1.10 for the announced revised-methodology transition, the unfinished live 2027 PolicyEngine run, and the limitation of calibrating volatility from only five annual changes: 5.8008 × 1.10 = 6.3809pp. Thus 13.2 ± 6.3809 = [6.8191, 19.5809], published as [6.8, 19.6]. Four of the five observed annual moves—80%—fit within ±6.3809pp.

Mechanism and counter-consideration: the condition reaches very-low-earning families by starting the ACTC phase-in near the first dollar, but the unchanged 15% rate limits the mechanical gain to roughly $375 and nonfiling can prevent take-up. The modeled -0.2pp effect is therefore applied once, not double-counted with the 2021 expanded-CTC observation. Upside risk would land above the interval if the revised SPM methodology sharply raises measured child poverty while a recession substantially reduces low-income earnings. Downside risk would land below the interval if unexpectedly strong earnings combine with much broader refundable-credit legislation or unusually complete filing take-up.

Review disposition: accepted both optional suggestions by clarifying that the -0.2pp PolicyEngine adjustment is a directional inside-view input rather than a completed 2027 estimate and by identifying the five-change volatility sample as an interval-calibration limitation. No required fixes were identified.

calibrated forecast · 80% CI
13.2%[6.8% · 19.6%]
Target metadata

Data point: census.spm.child_poverty_rate.2027.first_print.threshold_one_dollar

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