Scan: GDP growth in 2031? — 2.1% to 2.5%

date	predicted	market price	confidence
2026-08-29	13%	15%	62%
2026-08-22	14%	15%	59%
2026-08-04	12%	9%	38%

1. Planner Fable 5.1 · Fermi decomposition + tool plan

Tools chosen: kalshi_direct kalshi_related polymarket_related fred code_execution claude_news article_search

Sub-questions (Fermi decomposition)

What is the current Kalshi price for the 2.1%-2.5% bucket and how are the other 2031 GDP buckets priced (does the distribution sum sensibly after de-vigging)?
Historically (e.g., 1990-2024), what fraction of years had US annual real GDP growth (annual average or Q4/Q4, depending on Kalshi's resolution convention) falling within a 0.5-point band centered around 2.3%?
What are the CBO and Fed longer-run/potential real GDP growth projections for the late 2020s and early 2030s, and how far are they from the 2.1-2.5% range?
What is the standard deviation of annual US real GDP growth over the past few decades, and what probability does a normal/empirical distribution centered on potential growth assign to the 2.1-2.5% band roughly 6-7 years ahead?
Are there structural drivers (AI productivity, immigration/labor-force trends, demographics, fiscal policy) that forecasters currently argue will push trend growth above or below ~2% by 2031?
How does Kalshi price the analogous bucket for nearer years (2026-2030 GDP growth markets), and do those prices imply a consistent implied distribution?

Planner reasoning

This is a very long-horizon question (2031 real GDP growth, resolving early 2032), so current data has limited direct predictive power; the estimate should rest on the historical distribution of annual US real GDP growth, long-run potential growth estimates (CBO, Fed SEP longer-run), and the current Kalshi market price for this bucket and its siblings. The 2.1–2.5% bucket sits right around consensus potential growth (~1.8–2.0%), so the key questions are about the variance of annual growth outcomes and how the market prices adjacent buckets.

2. Research Parallel tool calls

tool	status	time	items	summary
kalshi_direct	OK	0.2s	1	## This Market's Kalshi Data 2.1% to 2.5% (KXGDPYEAR-31-B2.3) - Current price (probability): 15.00% - 7-day price change: +10.00% - 30-day price change: +4.00% - Average daily volume: 1306 contracts - Price range: 5.00% - 17.00% - Data points: 8 days
kalshi_related	OK	4.8s	3	3 related markets / summaries. series KXGDPYEAR: 0 markets (skipped 100 no-signal) \| keyword 'GDP growth 2031': ok \| keyword 'GDP growth 2030': ok \| keyword 'GDP growth 2029': ok
polymarket_related	OK	0.1s	0	Scanned 100 active Polymarket markets, kept 0 matches. keyword 'GDP growth': 0 markets \| keyword 'US GDP 2031': 0 markets \| keyword 'recession': 0 markets
fred	OK	5.8s	4	Fetched 4 FRED series (lookback=14600d).
code_execution	OK	32.4s	0	## Key Findings Empirical base rates for growth in [2.1%, 2.5%]: - Full sample (1950–2024, n=75): 12.0% of years fall in this band - 2000–2024 (n=25): 24.0% of years fall in this band (elevated due to steady mid-2010s growth) - 2010–2024 (n=15): 40.0% of years fall in this band — th
claude_news	OK	24.2s	13	## Key Findings CBO Long-Term Projections (most directly relevant to 2031): - In CBO's most recent long-run outlook (2025–2035), the economy grows at an average annual rate of 1.8 percent from 2027 to 2031, with growth beyond 2031 driven mainly by CBO's projection of real potential GDP (cbo.g
article_search	OK	4.9s	20	Fetched 20 unique articles across 3 queries (lookback=180d). 'US potential GDP growth long-run projection CBO': 8 articles \| 'AI productivity boost US trend growth forecast': 8 articles \| 'Fed longer-run GDP growth estimate SEP': 8 articles

3. Evidence Brief Sonnet 5 · 6163 chars

# Event Kalshi market KXGDPYEAR-31-B2.3 asks whether US real GDP growth in 2031 will fall in the 2.1%–2.5% bucket (one of several mutually exclusive GDP-growth-range buckets for that year). # Outcomes to forecast - Yes (2031 real GDP growth lands in 2.1%–2.5%) - No (growth falls outside that band) # Kalshi market anchor Current YES price: **15%** [kalshi_direct]. Trend: up sharply — 7-day change +10pp, 30-day change +4pp, with an 8-day observed range of 5%–17% [kalshi_direct]. Average daily volume ~1,306 contracts, moderate liquidity [kalshi_direct]. The rapid recent run-up (5%→15-17%) suggests either new information (e.g., Fed/CBO revisions) or repricing across the GDP-bucket family, not a stable long-run consensus. # Sub-question answers 1. **Current price / bucket distribution** — 2031 2.1-2.5% bucket = 15% [kalshi_direct]. Adjacent-year comparables: 2030 2.6-3.0% = 20%, 2036 2.6-3.0% = 9%, 2029 4.6-5.0% = 5% [kalshi_related]. Full 2031 bucket distribution (other ranges for 2031) was not retrieved, so de-vig sum-check is not possible with available data. 2. **Historical base rate (0.5pt band around 2.3%)** — 1950-2024: 12%; 2000-2024: 24%; 2010-2024 (most relevant recent regime): 40% [code_execution]. Actual 2025 annual growth was 2.1% (A191RL1A225NBEA), i.e., at the bucket's lower edge [FRED]. 3. **CBO/Fed longer-run projections** — CBO: potential GDP growth ~2.1%/yr (2026-2030) slowing to ~1.8%/yr (2031-2036); 2031 sits at the transition point [claude_news, cbo.gov/62105]. CBO's 2027-2031 actual-growth path averages ~1.8%/yr [cbo.gov/61189]. Fed SEP longer-run median = 1.8-2.0% (Dec 2025: 1.8; later 2026 revisions to 2.0%) [claude_news, federalreserve.gov]. Both sit at/below the low end of the 2.1-2.5% bucket. 4. **SD / normal-model probability** — Modern-era (1990-2024 ex-2020/21) mean ≈2.54%, SD≈1.46% [code_execution]. Normal-model P(land in [2.05,2.55]) given mean 1.9-2.2%, SD 1.2-2.0 ranges ~9.75%-16.5% [code_execution] — well below the empirical 2010-2024 base rate. 5. **Structural drivers (AI, demographics, fiscal)** — Mixed/contested: optimistic AI-productivity estimates (Acemoglu-style) imply +1.5pp/yr productivity boost over a decade; conservative estimates put AI's 2032 contribution at only +0.2pp [claude_news, tecunningham.github.io]. World Bank frames wide dispersion of 2030s growth scenarios depending on AI adoption [worldbank.org]. Fiscal/debt trajectory (debt >120% GDP by 2036) is a headwind cited by CBO/Washington Post [washingtonpost.com]. No clear consensus that trend growth exceeds ~2% by 2031. 6. **Nearer-year Kalshi buckets** — 2030 real GDP 2.6-3.0% priced at 20% (up sharply, 30-day +12pp) [kalshi_related]; 2029 4.6-5.0% priced at only 5%, declining [kalshi_related]; 2036 2.6-3.0% at 9% [kalshi_related]. These are different buckets/years so not directly comparable, but show markets pricing meaningful odds of above-trend growth in nearer years while the 2031 2.1-2.5% "moderate" bucket sits at 15%. # Key facts (high-confidence, factual) 1. [FRED A191RL1A225NBEA] Actual annual real GDP growth: 2025=2.1%, 2024=2.8%, 2023=2.9%, 2022=2.5%, 2019=2.6%, 2018=3.0%, 2017=2.5%, 2016=1.8%. 2. [CBO 62105] Potential GDP growth: 2.1%/yr (2026-30) → 1.8%/yr (2031-36). 3. [Fed SEP Dec 2025] Longer-run GDP median 1.8%, central tendency 1.8-2.0%. 4. [code_execution] Empirical base rate for 2.1-2.5% band: 40% (2010-2024), 24% (2000-2024), 12% (1950-2024). 5. [CBSNews 2026-04-30] Q1 2026 GDP grew ~2% annualized; 2025 full-year growth 2.1%. 6. [kalshi_direct] 2031 bucket YES price rose from 5% to 15-17% over past 30 days. # Cross-market signals - Kalshi related: 2030 similar "moderate-high" bucket (2.6-3.0%) priced 20% and rising fast (+12pp/30d); 2029 higher-growth bucket falling (5%, -2pp); suggests market sentiment currently favors moderate-to-softer growth paths across the curve, consistent with tariff/war-related drag narratives. - Polymarket: No matching markets found [polymarket_related]. - Sportsbook implied: N/A (economic data market). # Analyst opinions and speculation - EY-Parthenon (Daco): 2026 GDP growth downgraded to ~1.8% due to Iran-war oil shock [CBSNews 2026-04-30]. - SPF Q2 2026: 2026 GDP +2.2%, 2027 slowing to 1.9%, "bouncing back above 2%" thereafter [CNBC 2026-05-15] — loosely consistent with 2031 landing near/inside 2.1-2.5%. - IMF: upgraded global 2026-27 growth on AI/tech investment surge, flags AI productivity as key two-sided medium-term risk [IMF WEO Jan 2026]. - World Bank: AI could push 2030s growth above 2000s average under optimistic scenarios, or produce modest gains under conservative ones — wide uncertainty band. # Directional lean per outcome - **Yes (2.1-2.5%)**: Supported by 2010-2024 base rate (40%), 2025 actual growth exactly at 2.1%, CBO's near-term 2.1% potential estimate, SPF trajectory bouncing to "above 2%." Opposed by CBO's 2031-specific 1.8% central estimate, Fed longer-run median (1.8-2.0%), and normal-model probability estimates (10-16%), all clustering just below the bucket. - **No**: Favored by structural/potential-growth consensus (CBO, Fed) sitting below 2.1%, fiscal drag/debt concerns, and AI-productivity effects being contested/uncertain in magnitude and timing (peak effects modeled as late as 2032+). Also favored simply because a 0.4pp-wide bucket is narrow relative to typical year-to-year GDP volatility (SD~1.5-2pp), making any single bucket a minority outcome. # Gaps / unknowns - Full 2031 bucket distribution (all Kalshi buckets, not just 2.1-2.5%) not retrieved — cannot confirm de-vigged sum to 100%. - Kalshi's exact resolution convention (annual average vs. Q4/Q4) not specified in rules. - No Polymarket or sportsbook cross-check available. - Reason for the sharp 5%→15-17% price move in past 30 days not explained by retrieved news. # Calibration anchors - Kalshi current YES price: **15%** (anchor). - Empirical base rate 2010-2024: 40%; normal-model estimate: 10-16%; blended synthesis estimate from research: ~20-30%. - CBO/Fed central "trend" estimates (1.8-2.0%) sit just below the bucket, arguing for a probability toward the lower-middle of that blended range (roughly 15-22%).

4. Forecasters Fable 5.1 + GPT-5.6 Sol · in parallel

claude-fable-5-1

35% conf

Yes	18%
No	82%

The Kalshi anchor is 15%, and a 0.5pp-wide bucket is narrow relative to year-to-year GDP volatility (SD ~1.5pp), so normal-model estimates land around 10-16%. However, the bucket sits near the modal region of recent stable-year outcomes (2010-2024 base rate 40%, 2025 actual 2.1%, CBO near-term potential 2.1%), and real GDP outcomes cluster around 2-3% more tightly than a normal model implies, arguing for a modest lift above the market. CBO/Fed 2031 trend estimates (1.8-2.0%) sit just below the bucket and fiscal/oil-shock headwinds favor No, so I only nudge slightly above the anchor to ~18%.

gpt-5.6-sol

58% conf

Yes	18%
No	82%

The 15% Kalshi YES price is the primary anchor, although its sharp recent rise and the missing full bucket distribution make it less stable. Historical evidence is mixed: the band occurred in 40% of 2010–2024 observations, but longer samples and volatility-based models imply only about 10%–24%. CBO and Fed longer-run projections center on 1.8%–2.0%, pointing just below the bucket, while the SPF rebound above 2% and uncertain AI productivity gains provide some upside. Because the interval is narrow relative to annual GDP volatility, I move only modestly above the market to 18%.

5. Devil's Advocate Sonnet 5 · red-team critique

Both forecasters converge on identical 18% estimates despite the brief noting a "blended synthesis estimate from research: ~20-30%" — neither explains why they landed well below this synthesis range rather than near its midpoint.

Neither forecaster grapples with the sharp 5%→15-17% price momentum (+10pp in 7 days) as a potential signal of new information (e.g., Fed/CBO revision, tariff news) that could argue for weighting the anchor's *trend* more heavily rather than treating 15% as a static anchor to nudge from.

Both ignore the "Gaps/unknowns" caveat that the full 2031 bucket distribution wasn't retrieved and de-vig couldn't be checked — if adjacent buckets are overpriced/underpriced due to the same recent repricing wave, the 15% anchor itself may be systematically biased, which neither rationale addresses.

Neither forecast weighs the asymmetry that CBO's own 2031 estimate (1.8%) is a transition-year midpoint between two distinct regimes (2.1% pre-2031, 1.8% post-2031), meaning 2031 itself is structurally ambiguous and could plausibly still average near 2.0-2.1%, which is closer to the bucket's lower edge than the "just below" framing suggests — this nuance is glossed over identically by both.

Both cite the 40% empirical base rate (2010-2024) as directionally supportive but discount it almost entirely in favor of the model-based 10-16% range without justifying why the more medium-term regime-relevant empirical rate should be weighted so lightly, especially given 2025's actual print (2.1%) sat exactly at the bucket's edge.

Neither forecaster addresses the cross-market signal that the 2030 bucket (2.6-3.0%) is priced at 20% and also rising fast (+12pp/30d) — if adjacent buckets are inflating together, this could reflect a systematic upward repricing of moderate-growth buckets rather than idiosyncratic information about 2031, a consideration that would argue for more caution in trusting the anchor's recent momentum.

6. Aggregator Fable 5.1 · final calibrated forecast

20% (46% confidence)

Yes: 20% No: 80%

Both forecasters independently landed at 18%, anchored on the 15% Kalshi price and a normal-model estimate (10-16%) for a narrow ~0.5pp bucket five years out. The critique correctly notes that the bucket sits at the modal region of recent stable-year outcomes (2010-2024 base rate ~33-40%, 2025 actual 2.1%, CBO near-term potential 2.1%) and that CBO's 2031 figure is a regime-transition midpoint plausibly averaging near 2.0-2.1%, so the empirical clustering deserves somewhat more weight than a pure normal model gives it. Offsetting this, five-year-ahead GDP uncertainty is large, Fed/CBO trend estimates sit just below the band, and the market's recent 5%→15% jump on thin long-dated liquidity is not a reliable signal in either direction. I nudge slightly above both forecasts to 20% Yes, staying well below the raw 2010-2024 base rate because that sample excludes recessions and regime shifts that a 2031 forecast must price.

Pipeline Timing

Total pipeline time: 139.9s

Per-tool research timings shown in the Research section above.