Scan: GDP growth in 2033? — 0.1% to 0.5%

date	predicted	market price	confidence
2026-08-27	8%	9%	67%
2026-08-20	6%	9%	64%
2026-07-30	4%	25%	50%

1. Planner Fable 5.1 · Fermi decomposition + tool plan

Tools chosen: kalshi_direct kalshi_related fred code_execution claude_news polymarket_related

Sub-questions (Fermi decomposition)

What is the current Kalshi YES price for the 0.1%-0.5% bin, and what distribution across all KXGDPYEAR-33 bins do the sibling market prices imply (do they sum near 100%)?
Over 1948-2024, in what fraction of years did US annual real GDP growth (BEA annual, series A191RL1A225NBEA) fall between 0.1% and 0.5% inclusive, and how does that compare with adjacent bins?
What are the long-run consensus projections (CBO long-term outlook, Fed SEP longer-run growth, SPF 10-year) for US potential real GDP growth around 2033, and what is the historical standard deviation of annual growth around trend?
Given a mixture model (expansion years centered ~2% with sd ~1.2, plus ~15% recession-year probability), what probability mass lands in the 0.1%-0.5% band?
Does the market resolve on annual-average real GDP growth (BEA annual) or Q4/Q4 growth, and does the initial/advance estimate or a revised estimate count, given the Feb 2034 close time?
Are there other Kalshi or Polymarket markets on long-dated US GDP growth (e.g., KXGDPYEAR for 2026-2032) that show how the crowd prices near-zero bins for far-out years?

Planner reasoning

This is a very long-horizon question (resolves ~10 years out), so current macro data has little predictive value; the estimate should be driven by the historical base rate of annual US real GDP growth landing in a narrow 0.4pp bin just above zero, adjusted for a long-run trend of ~1.8-2.0% and the shape of the growth distribution (recessions tend to push growth negative rather than into the 0.1-0.5% band). The Kalshi price and the implied distribution across sibling bins in KXGDPYEAR-33 are the primary anchor, and I want to check whether the market is pricing the tails and near-zero bins sensibly versus history.

2. Research Parallel tool calls

tool	status	time	items	summary
kalshi_direct	OK	0.1s	1	## This Market's Kalshi Data 0.1% to 0.5% (KXGDPYEAR-33-B0.3) - Current price (probability): 9.00% - 7-day price change: -6.00% - 30-day price change: -1.00% - Average daily volume: 1855 contracts - Price range: 3.00% - 15.00% - Data points: 9 days
kalshi_related	OK	4.1s	2	2 related markets / summaries. series KXGDPYEAR: 0 markets (skipped 100 no-signal) \| keyword 'GDP growth 2033': ok \| keyword 'GDP growth': ok
fred	OK	5.5s	6	Fetched 6 FRED series (lookback=30000d) (via search 'real GDP annual percent change').
code_execution	OK	43.6s	0	## Findings: US Real GDP Growth Falling in [0.1%, 0.5%] Range Historical base rates (BEA A191RL1A225NBEA, annual % change): - Full sample 1948–2024 (77 years): only 2/77 = 2.60% of years fall in [0.1, 0.5] — specifically 1970 (0.2%) and 2008 (0.1%) - Subset 1980–2024 (45 years): onl
claude_news	OK	31.5s	8	Here are the key findings: CBO Long-Term Projections - CBO's 2025 Budget and Economic Outlook: real GDP grows by 1.8 percent per year, on average, through 2035, with roughly four-fifths of the growth over that period due to increases in the productivity of the labor force. (https://www.cbo.go
polymarket_related	OK	4.0s	0	Scanned 100 active Polymarket markets, kept 0 matches. keyword 'GDP growth': 0 markets \| keyword 'US GDP 2033': 0 markets \| keyword 'recession': 0 markets

3. Evidence Brief Sonnet 5 · 6721 chars

# Current state Kalshi's KXGDPYEAR-33-B0.3 market prices the 0.1%–0.5% real GDP growth bucket for 2033 at 9% YES, down from a 30-day high of 15% and a 7-day drop of 6pp. This is a far-dated (resolves Feb 2034), thinly-informative market where no 2033-specific data exists yet; pricing reflects generic priors about long-run growth distribution, not new information. # Timeline of key events - 2025-02 (confirmed): BEA advance Q4 2025 release reports Q4 growth 1.4%; full-year 2025 real GDP growth 2.1% (FRED A191RL1A225NBEA). - 2025 (confirmed): CBO's 2025 Budget and Economic Outlook projects average real GDP growth ~1.8%/yr through 2035; potential GDP growth ~2.2% (2025-29) then ~1.9% (2030-35). - 2025-12 (confirmed): Fed December SEP median longer-run real GDP growth = 1.8%, central tendency 1.8–2.0%. - 2026 (reported): CBO's 2026–2036 outlook update — near-term 2026 growth revised up (reconciliation act effects) but later-year (into early 2030s) trajectory "generally the same," ~1.8–1.9%. - 2026-mid (reported): Fed June SEP reaffirms longer-term potential growth ~2.0%. - 2026 Q2/Q3 (confirmed): Philly Fed SPF projects 2026 growth ~2.2%, and 2026-2029 annual-average growth 2.1–2.4%. - Recent 9 days (confirmed, Kalshi): B0.3 bucket price fell from 15% to 9% (30-day range 3–15%), volume ~1855 contracts/day average — active but not deeply informative given 2033 is 7+ years out. # Event Kalshi market KXGDPYEAR-33-B0.3: will US real GDP growth in 2033 fall between 0.1% and 0.5% (inclusive)? # Outcomes to forecast - Yes (growth lands in 0.1%–0.5%) - No (growth lands elsewhere) # Kalshi market anchor Current YES price: **9%**. 7-day change: -6pp (was ~15%). 30-day change: -1pp. Price range over data window: 3%–15%. Average daily volume: 1,855 contracts (relatively liquid for a niche bucket). [kalshi_direct] # Sub-question answers 1. **Kalshi price/sibling distribution?** — This bucket (B0.3) is priced at 9%. The only sibling series data retrieved is for different years (2035 B1.8 at 13%, 2036 B2.8 at 9%) — no full 2033 bucket ladder was returned, so we cannot confirm sibling bins sum to ~100%. [kalshi_related] 2. **Historical base rate 1948-2024?** — Only 2/77 years (2.6%) landed in [0.1%,0.5%]: 1970 (0.2%) and 2008 (0.1%); 1980-2024 subset gives 1/45 (2.2%). This is a sparse "valley" between recession and trend-growth clusters. [code_execution/FRED] 3. **Consensus long-run projections?** — CBO: ~1.8-1.9%/yr average into early 2030s; Fed SEP longer-run: 1.8-2.0% median; SPF 2026-2029: 2.1-2.4%. All well above the 0.1-0.5% band. No source isolates 2033 specifically. [claude_news/CBO/Fed/SPF] 4. **Mixture model estimate?** — Baseline mixture (15% recession @ N(-1.0,1.5), 85% expansion @ N(1.9,1.1)) gives P(0.1≤g≤0.5) = 5.4%; sensitivity range 3.4%-7.4% depending mainly on expansion mean assumption. [code_execution] 5. **Resolution basis (annual vs Q4/Q4, vintage)?** — Unconfirmed. Kalshi's public rulebook text wasn't retrievable; likely uses BEA annual-average % change (standard convention), but which release vintage (advance/second/final) counts is unknown given Feb 2034 close (allows time for at least the advance Feb 2034 release, ~1 month post year-end). [claude_news — explicitly flagged as unconfirmed] 6. **Other long-dated GDP bins for context?** — 2036 B2.8 (2.6-3.0%) priced at 9%; 2035 B1.8 (1.6-2.0%) priced at 13%. These trend-centered bins are priced similarly or higher than the near-zero 2033 bin, suggesting market doesn't strongly discount near-zero outcomes for far-out years relative to trend bins. [kalshi_related] # Key facts (high-confidence, factual) 1. [kalshi_direct] Current YES = 9%, down from 15% high in past 30 days. 2. [FRED A191RL1A225NBEA] 2025 annual growth = 2.1%; 2024 = 2.8%; 2023 = 2.9%. 3. [code_execution] Only 2 of 77 years (1948-2024) fell in [0.1%,0.5%]; band is a statistical "valley," not a common outcome. 4. [CBO/Fed/SPF] Consensus long-run trend growth estimates cluster 1.8-2.4%, well above target bucket. 5. [code_execution] Mixture-model central estimate: ~5% probability mass in target band. # Cross-market signals - Kalshi related: 2035 (1.6-2.0%) bucket = 13% YES; 2036 (2.6-3.0%) bucket = 9% YES — both trend-centered bins priced comparably to this near-zero 2033 bin, implying crowd may be somewhat under-differentiating tail vs. central bins for distant years. - Polymarket: No matching GDP/recession markets found (0 matches across 3 keyword searches). No cross-check available. - Sportsbook implied: N/A (not applicable to economic data market). # Analyst opinions and speculation - claude_news synthesis: baseline trend forecasts (CBO, Fed, SPF) all sit meaningfully above the 0.1-0.5% bracket, implying this outcome would require a recession-adjacent/below-trend year specifically threading a narrow near-zero-but-positive needle — historically rare. - code_execution synthesis: converges on "low-probability outcome, roughly 3-6%" from both empirical base rate and mixture modeling, independent of Kalshi's own price. # Directional lean per outcome - **Yes (9% Kalshi):** Supporting — none strong; band exists as a possible/available outcome, market volume suggests some genuine liquidity/interest. Opposing — historical base rate (~2-3%), mixture-model estimate (~5%), and consensus trend forecasts (1.8-2.4%) all indicate this bucket is a low-density "valley," suggesting fair value likely below or near current 9% price, possibly overpriced. - **No (would be ~91% if binary):** Supported strongly by historical frequency data, structural trend forecasts, and mixture modeling — all pointing to growth more likely landing either negative/recession territory or in the 1.5%+ trend range, skipping the narrow 0.1-0.5% band. # Gaps / unknowns - Exact Kalshi resolution rule (annual-average vs Q4/Q4; which BEA vintage) unconfirmed — could materially affect base-rate applicability if Q4/Q4 is used (more volatile, different historical hit rate). - No 2033-specific forecast exists (earliest CBO/SPF/Fed horizons only reach ~2029-2036 in aggregate, not isolating 2033). - Full ladder of 2033 sibling Kalshi buckets not retrieved, so can't verify implied distribution sums to 100% or benchmark relative bucket pricing. - No Polymarket cross-check available. # Calibration anchors - Kalshi current YES price: **9%** (anchor). - Historical base rate for this band (1948-2024): ~2.6% (2/77 years); 1980-2024: ~2.2% (1/45). - Mixture-model estimate: ~3.4%-7.4%, central ~5.4%. - Precedent: adjacent trend-centered bins (2035, 2036) priced 9-13%, suggesting market may not be sharply discounting narrow near-zero bins relative to base-rate evidence — implies possible mispricing/overpricing of this Yes outcome.

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

claude-fable-5-1

45% conf

Yes	6%
No	94%

Kalshi prices the 0.1–0.5% bucket at 9%, but the brief's independent evidence points lower: only 2 of 77 years since 1948 (2.6%) landed in this narrow near-zero-but-positive 'valley,' and a recession/expansion mixture model centered on CBO/Fed trend growth (~1.8–2.0%) yields ~5.4% (range 3.4–7.4%). Far-dated Kalshi bins tend to be inflated by low liquidity and time-value effects, and the fact that trend-centered 2035/2036 bins are priced no higher than this tail bin suggests under-differentiation. I shade below the market anchor toward the model/base-rate estimates while leaving room for the wide 7-year uncertainty and unconfirmed resolution convention (annual vs Q4/Q4).

gpt-5.6-sol

66% conf

Yes	6%
No	94%

The Kalshi YES anchor is 9%, but the incomplete sibling ladder limits how confidently that price can be interpreted. Historically, only 2 of 77 years landed in this narrow band, while the mixture model assigns it about 5.4% with a 3.4%–7.4% sensitivity range. CBO, Fed, and SPF projections center long-run growth around 1.8%–2.4%, making 0.1%–0.5% a recession-adjacent valley rather than a typical outcome. I therefore mark YES below the market at 6%, while retaining uncertainty because the 2033 macro environment and exact resolution convention are unknown.

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

Both forecasts converge tightly on ~6-6.5%, essentially just averaging the base-rate/mixture-model figures, but neither meaningfully engages with the resolution-rule uncertainty flagged in the brief ("unconfirmed... could materially affect base-rate applicability if Q4/Q4 is used") — if Q4/Q4 is used, volatility is higher and the historical hit-rate for this specific band could differ substantially from the annual-average base rate they both lean on.

Neither forecaster grapples with the 7-year-out uncertainty compounding: CBO/Fed/SPF consensus (1.8-2.4%) is a point estimate, but 2033 is far enough out that a recession, supply shock, or structural growth-rate shift is plausible and could shift the mixture weights (e.g., recession probability by year 8 of a cycle) — both treat the 15%/85% recession/expansion split as settled rather than flagging its own uncertainty.

Both forecasts dismiss the Kalshi price (9%) as likely inflated/overpriced without asking why liquidity is meaningfully active (~1,855 contracts/day) if this is truly a low-information "generic prior" market — some real money may be pricing information both forecasters lack (e.g., market-specific resolution nuances or fat-tail scenarios), yet neither forecaster interrogates the divergence's plausibility (is it liquidity noise or genuine informed money?).

Neither forecaster addresses the recent 7-day price drop (15%→9%) as a directional signal — was this driven by news, or is it noise given "thinly-informative" pricing? If it's noise, converging on 6% (below even the post-drop 9%) may be overconfident; if it's informed, it modestly validates their below-market lean but they don't explain the mechanism.

Both cite the incomplete sibling ladder as a limiting factor but then proceed as if the mixture model and base rate are sufficient without weighting the missing bucket-sum-to-100% check, which could reveal whether 9% is actually a locally low or high price relative to adjacent bins (the brief notes 2035/2036 bins priced 9-13%, comparable, but doesn't confirm the full 2033 ladder itself sums correctly, which is a distinct diagnostic gap).

Forecast 2's stated confidence (0.66) versus Forecast 1's (0.45) diverge substantially despite near-identical point estimates and reasoning — neither explains why their confidence in the underlying model differs, which is an internal inconsistency in how much epistemic weight to place on a fundamentally unconfirmed 2033-specific forecast.

6. Aggregator Fable 5.1 · final calibrated forecast

7% (56% confidence)

Yes: 7% No: 93%

The 0.1%–0.5% band is a historically sparse 'valley' between recession and trend-growth outcomes (2/77 years since 1948), and a recession/expansion mixture model centered on CBO/Fed/SPF long-run growth (~1.8–2.4%) yields roughly 5.4% (3.4–7.4% range). Kalshi prices YES at 9%, but far-dated bins in thin markets are typically inflated by time-value and uninformed flow, and the comparably priced trend-centered 2035/2036 bins suggest the crowd is under-differentiating tails from central bins. The critique correctly notes unresolved uncertainty about resolution convention (annual vs Q4/Q4) and about recession-weight compounding over a 7-year horizon, which argues against going all the way to the historical base rate. I therefore land at 7%—between the model estimate and the market anchor—giving modest weight to the market's liquidity while leaning on the structural evidence that this narrow band is a low-density outcome.

Pipeline Timing

Total pipeline time: 140.8s

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