CPI inflation on Polymarket: YoY, MoM, headline and core

In BLS materials, headline generally refers to all items and core to the index excluding food and energy. The reviewed Core CPI MoM contract explicitly selects the latter. Do not substitute overall inflation because a news article reports it first.

Also check CPI-U, geographical coverage and seasonal adjustment. Another country's consumer inflation, a PCE index or one component of the US basket cannot automatically answer the same question.

MoM compares with the previous month; YoY compares with the same month one year earlier. An index level also differs from its percentage change. A single release may contain both periods, so choose the correct column instead of a convenient number.

Illustrative example: 0.3% over one month and 3.0% over one year can coexist. Multiplying the latest monthly change by 12 does not reconstruct the actual annual figure or replace the contract's specified measurement.

Check whether the market asks for an exact published value, a bracket or a threshold exceedance. The reviewed Core CPI contract uses one decimal place from the BLS release. Extra digits from your own calculation do not override its predefined precision.

More than 3.0 and 3.0 or more differ at equality. Read grouped outer options as well. The threshold is the condition; the market percentage estimates whether that condition will be met.

Seasonally adjusted CPI series can be revised when seasonal factors are updated annually. Ordinary unadjusted CPI-U follows a different procedure, with error corrections possible. Neither CPI never changes nor automatically substituting a later vintage into an old contract is sound.

Keep the initial release, reference period and revision clause. If publication is delayed, inspect the exceptional provision. The reviewed market defines its own fallback; it does not establish a policy for every inflation question on the platform.