Tools chosen: kalshi_direct kalshi_related fred code_execution claude_news polymarket_related

Sub-questions (Fermi decomposition)

Planner reasoning

This is a very long-horizon macro question (2031 annual US real GDP growth landing in the 2.1–2.5% bucket), so the dominant inputs are (a) the current Kalshi price and the shape of the full bucket ladder, and (b) a historical base rate for annual real GDP growth falling in a 0.4pp-wide band around ~2.3%, cross-checked against CBO/Fed long-run potential growth projections. I'll anchor on the market, pull the sibling buckets for the implied distribution, get historical GDPC1 annual growth for base-rate math, and use code execution to compute the probability of the band under a plausible distribution.

# Current state Kalshi's KXGDPYEAR-31-B2.3 market prices the "2.1%–2.5%" 2031 real GDP growth bucket at 8% YES, down from ~11% a month ago. This is a far-dated, thinly-informed contingent contract (2031 outcome, resolving 2032) with no actual 2031 data yet — pricing is model/base-rate driven, not evidence-driven. # Timeline of key events - 2025-01-01: 2024 full-year real GDP growth reported at 2.8% (BEA A191RL1A225NBEA, confirmed). - 2025-01-01 (annual, prior year): 2025 growth pace given as 2.1% per one annual series entry (BEA, confirmed) — note conflicting quarterly data shows a volatile 2025 (Q1 -0.6%, Q2 3.8%, Q3 4.4%, Q4 0.5%) (FRED, confirmed). - 2025-12-10: FOMC December SEP: longer-run real GDP growth median 1.8%, central tendency 1.8–2.0%, range 1.7–2.5% (NY Fed, confirmed). - 2026 (published): CBO "Budget and Economic Outlook 2026–2036" projects potential GDP growth averaging 2.1%/yr (2026–2030) slowing to 1.8%/yr (2031–2036) due to slower labor productivity growth (CBO, confirmed). - 2026-06: FOMC June SEP keeps longer-run median at 1.8%; near-term 2026-2028 growth estimates revised slightly down (2.2–2.3%) (FRED Blog, confirmed). - 2026-07: Deloitte revises 2030 US GDP growth forecast up to 2.1% (from 1.7% in March), citing AI productivity gains (Deloitte, reported). - Current (as of research): Kalshi 2031 bucket price 8%, having fallen from 11% over past 30 days (Kalshi, confirmed). # Event Will actual US real GDP growth in calendar year 2031 fall between 2.1% and 2.5% (inclusive lower bound)? # Outcomes to forecast - Yes (2031 growth lands in 2.1%–2.5%) - No (growth outside this band) # Kalshi market anchor YES price: **8%** (as of latest data), down from 11% 30 days ago and down from 11% 7 days ago (steady decline). Price range over observed window: 5%–11%. Average daily volume: 1,819 contracts — moderate liquidity for a long-dated bucket market. [kalshi_direct] # Sub-question answers 1. **Current Kalshi price/volume** — YES = 8%, 7-day and 30-day change both -3pp, avg daily volume 1,819 contracts, 5 days of data observed. [kalshi_direct] 2. **Ladder/full distribution implications** — Full 2031 ladder not directly retrieved; related-year buckets (2034/2035 "1.6–2.0%" priced 9–10%, 2036 "6.1%+" priced 12%) suggest the market spreads probability thinly across many buckets with no single bucket dominating, consistent with wide, low-conviction distributions this far out. Cannot confirm sum-to-1 de-vig. [kalshi_related] 3. **Historical base rate (1950–2024, proxy)** — ~10.7% of years fell in 2.1–2.5% (8/75); 1985–2024 ~12.5%; 1995–2024 ~16.7% (recent decades trend higher, consistent with slower trend growth). [code_execution, illustrative/approximate] 4. **CBO/FOMC long-run projections & volatility** — CBO's newest outlook: potential growth 2.1%/yr avg 2026–2030, decelerating to **1.8%/yr for 2031–2036** — implying 2031 itself likely near/just below the 2.1% floor. FOMC longer-run median is 1.8% (range 1.7–2.5%). Historical annual growth sd is ~1.6–2.0pp. [claude_news/CBO/FOMC] 5. **Nearby-year Kalshi pricing** — 2034/2035 buckets for "1.6–2.0%" priced 9–10% (not directly comparable bucket); no direct 2.1–2.5% comparator found for adjacent years in retrieved data, limiting direct comparison of uncertainty-widening across years. [kalshi_related] 6. **Structural growth-shifting factors** — AI is a modest, not transformative, upside driver per most institutions: Goldman most bullish (2.3% avg early 2030s), Penn Wharton conservative (+0.2pp peak contribution in 2032), Deloitte revised 2030 up to 2.1%. CBO's own trajectory still shows deceleration to 1.8% by 2031-36 despite acknowledging AI investment boost. No major analyst projects sustained >2.5% growth for 2031. [claude_news] # Key facts (high-confidence, factual) 1. [Kalshi] Current YES price for 2.1–2.5% 2031 bucket: 8%, down from 11% (30d). 2. [CBO 2026] Potential GDP growth projected to average 1.8%/yr for 2031–2036, below the 2.1% floor of this bucket. 3. [FOMC Dec 2025/June 2026 SEP] Longer-run median growth estimate: 1.8%. 4. [BEA/FRED] 2024 actual growth: 2.8%; recent years volatile (2023: 2.9%, 2022: 2.5%, 2021: 6.2%, 2020: -2.1%). 5. [Goldman Sachs] Most bullish institutional forecast: 2.3% avg early 2030s — still below the 2.5% ceiling but above CBO/Fed baseline. # Cross-market signals - Kalshi related: 2034/2035 "1.6–2.0%" buckets priced 9–10%; 2036 "6.1%+" bucket priced 12% (rising +5pp in 7 days) — suggests some tail-risk repricing but limited direct read-across to the 2.1–2.5% 2031 bucket. - Polymarket: No matching GDP markets found (0/100 scanned). - Sportsbook implied: N/A (not applicable to this event type). # Analyst opinions and speculation - CBO/FOMC baseline view: trend growth decelerating toward ~1.8% by early 2030s due to slowing labor productivity/labor force growth — pulls probability mass toward the "below 2.1%" outcome, not into this bucket. - Goldman Sachs (bullish outlier): AI-driven productivity could push potential growth to 2.3% in early 2030s — squarely inside this bucket if realized, with upside AGI scenario possibly pushing above 2.5%. - Penn Wharton (bearish on AI impact): AI contributes only ~0.2pp by 2032, insufficient to offset structural deceleration. - Deloitte: raised 2030 forecast to 2.1%, right at the bucket's lower edge, reflecting incrementally more optimistic private-sector views. # Directional lean per outcome - **Yes (2.1–2.5%)**: Supported by Goldman's 2.3% projection and historical base rate (~13-17% in modern era) if growth surprises to the upside; also plausible if actual growth comes in right at CBO's 2026-2030 pace (2.1%) rather than fully decelerating. Opposed by CBO's explicit 1.8% avg for 2031-2036 and FOMC's 1.8% longer-run median — both point below this bucket's floor. Kalshi's declining price (11%→8%) suggests market losing confidence in this outcome. - **No**: Supported by convergence of CBO and FOMC on ~1.8% trend, historical base rate showing this specific 0.4pp band is inherently low-probability (any single narrow bucket rarely exceeds ~15-20%), and multiple other buckets (below 2.1%, i.e., 1.6-2.0% or lower) likely capturing more probability mass given trend deceleration consensus. # Gaps / unknowns - Full Kalshi ladder for 2031 (all buckets) not retrieved — cannot confirm de-vigged distribution or identify which bucket holds plurality probability. - No decomposed 2031-specific point-forecast from CBO/FOMC/Goldman (most cited ranges are averages over multi-year windows, e.g. 2031-2036 or "early 2030s"). - Base-rate figures from code_execution are explicitly a reconstructed/illustrative proxy series, not verified official BEA data — treat with caution. - No Polymarket or sportsbook cross-check available. # Calibration anchors - Kalshi current YES price: **8%** (anchor, declining trend). - Historical unconditional base rate for a similar ~0.4pp-wide bucket: ~11-17% (1950-2024 to 1995-2024 subsamples). - Model-based (Normal/Student-t) central estimates: ~12-16%. - CBO/FOMC trend-growth consensus (~1.8% for early 2030s) sits below this bucket's lower bound, arguably justifying pricing below the historical unconditional base rate — consistent with Kalshi's 8% (below the ~13-15% "naive" estimate).

1. Both forecasts converge tightly (0.10–0.11) and essentially just nudge slightly above the Kalshi anchor without independently grappling with the actual annual-volatility evidence: the brief notes 2022-2024 actual prints were 2.5%, 2.9%, 2.8% — all near or above this band — yet neither forecast weighs recent-year realized volatility against the smoothed CBO/FOMC "potential growth" trend, which is a distinct concept from actual annual growth and tends to understate single-year variance. 2. Neither forecaster explicitly notes that CBO/FOMC figures (1.8%) are *potential* or *longer-run* growth estimates, not point forecasts for the specific calendar year 2031 — the brief flags this gap directly ("No decomposed 2031-specific point-forecast from CBO/FOMC/Goldman"), so anchoring so heavily on 1.8% may overstate confidence in the No case. 3. Both treat the historical base rate (~11-17%) as a soft ceiling/reference but don't reconcile why they land near the *low* end (10-11%) rather than the middle of that range, given the brief's explicit note that recent decades (1995-2024) show a higher 16.7% rate — this recency-weighted base rate arguably deserves more weight than the 1950-2024 average. 4. Neither forecast interrogates the reliability of the Kalshi anchor itself: with only "5 days of data observed" and thin volume (1,819 contracts) on a market resolving in 2032, the 11%→8% decline could reflect noise or a single large order rather than genuine information — both forecasters treat the anchor as near-authoritative rather than discounting for its stated thinness. 5. Neither addresses the ladder/distribution-consistency check flagged in the brief (sub-question 2) — if adjacent buckets like "1.6–2.0%" are priced 9-10% and this bucket at 8%, that's suspiciously flat across buckets that should differ given the CBO's explicit skew toward sub-2.1% growth, suggesting a possible mispricing or de-vig issue neither forecast flags or corrects for. 6. Both forecasts ignore tail-scenario reasoning entirely (e.g., recession, AI-driven productivity boom, fiscal shock) despite historical annual sd of 1.6-2.0pp implying real width to the outcome distribution — high-uncertainty macro conditioning that far out arguably warrants a wider confidence interval on the probability estimate itself (e.g., 8-15%) rather than convergence to a near-point estimate of 10-11%.

12% (low-medium confidence)

Yes: 12% No: 88%

A 0.4pp-wide bucket sitting just above consensus trend growth is inherently low-probability: a normal model with mean ~1.9–2.0% and annual sd of 1.3–1.8pp yields 9–13% for this band, bracketing both the Kalshi anchor (8%) and the recency-weighted historical base rate (~13–17%). The critique correctly notes that CBO/FOMC 1.8% figures are potential/longer-run estimates rather than 2031 point forecasts, and that the thin, 5-day-observed Kalshi price decline (11%→8%) deserves discounting — both arguments push modestly above the market. Offsetting that, actual realized growth would need to land in a narrow window above the deceleration consensus, and no institution except Goldman (2.3%) projects inside the band, so the bulk of mass belongs on No (spread across sub-2.1% buckets and, less likely, above 2.5%). I settle at 11.5% Yes, slightly above both forecasters and meaningfully above the market anchor to reflect anchor thinness and recency-weighted base rates, while respecting the wide genuine uncertainty.

Total pipeline time: 136.3s