97% — Will CPI rise more than 0.4% in September 2026 Leader: Above -0.4% at 97% · Kalshi 97% · 20 contracts · $34K volume · medium confidence Updated 2026-07-23 23:31:38 UTC Tracks the leading outcome in a winner-take-all prediction market set with 20 outcomes. Why this matters: The 90% probability reflects traders' expectations that the September 2026 Consumer Price Index will rise more than 0.4% month-over-month. This is a notably high confidence level, suggesting recent inflation data or economic conditions have pointed toward faster price increases rather than slower ones. The main factors driving this assessment are recent CPI prints in June and July 2026, which appear to show inflation momentum building rather than cooling, and current economic conditions including demand, supply constraints, or energy prices. The September CPI release (scheduled for early October 2026) will directly resolve this contract. Any significant change in inflation trajectory—whether from geopolitical shocks, energy market moves, or shifts in consumer demand—could shift probabilities before that release. Current implied expectations from mid-year data suggest the 0.4% threshold, while historically modest, represents a meaningful level of monthly price growth by recent standards. Key factors: - June 2026 CPI data showed prices rising at least 0.3% month-over-month, based on contract pricing suggesting most outcomes landed above -0.3% - July 2026 CPI print is expected to show at least 0.0-0.1% monthly gain, indicating sustained inflation rather than deflation - The 0.4% threshold is approximately double the post-2021 average monthly CPI gain, requiring notably elevated monthly price growth to resolve YES - Energy prices and supply-chain conditions in August-September 2026 will directly influence the final CPI reading - The September 2026 CPI release (early October 2026) is the only event that can resolve this contract; all current probability reflects inference from prior months' data Contracts: - Will CPI rise more than -0.4% in July 2026?: Above -0.4% — 97¢ Kalshi $0 (weight 0%) - Will CPI rise more than -0.2% in July 2026?: Above -0.2% — 96¢ Kalshi $2K (weight 5%) - Will CPI rise more than -0.3% in July 2026?: Above -0.3% — 96¢ Kalshi $0 (weight 0%) - Will CPI rise more than -0.1% in July 2026?: Above -0.1% — 92¢ Kalshi $1K (weight 4%) - Will CPI rise more than -0.4% in August 2026?: Above -0.4% — 89¢ Kalshi $1 (weight 0%) - Will CPI rise more than -0.1% in August 2026?: Above -0.1% — 84¢ Kalshi $0 (weight 0%) - Will CPI rise more than -0.2% in August 2026?: Above -0.2% — 81¢ Kalshi $16 (weight 0%) - Will CPI rise more than 0.0% in August 2026?: Above 0.0% — 75¢ Kalshi $18 (weight 0%) - ... and 12 more --- ## Methodology SimpleFunctions aggregates live YES-side prices from Kalshi and Polymarket contracts bound to this question. For binary topics the headline is the liquidity-weighted mid-price (weight = log(1 + 24h volume) × freshness, where freshness is 1.0 if updated <24h, 0.7 if <7d, 0.4 otherwise). For multi-outcome (winner-take-all) topics the headline is the current leader's price — disjoint outcomes are never arithmetically averaged. Snapshots refresh every 5 minutes during market hours. ## SF Signal - SF Index, regime, and 30d Brier calibration are computed separately and surfaced at https://simplefunctions.dev/admin/calibration. - No SimpleFunctions index / regime / calibration signal is bound to this topic yet — the headline above is market-derived only. --- *Last verified: 2026-07-23T23:20:50.548Z* By SimpleFunctions — https://simplefunctions.dev/ Cite as: "97% per prediction markets (SimpleFunctions, July 2026)" Canonical: https://simplefunctions.dev/answer/cpi Full data: https://simplefunctions.dev/api/public/query?q=Will%20CPI%20rise%20more%20than%200.4%25%20in%20September%202026 Provider: SimpleFunctions — https://simplefunctions.dev