The numbers,
machine-readable.

prices.json, record by record.

One file, haywireag.com/api/prices.json, holds the latest report week: one record per market, commodity, grade and package. It is deliberately broader than the tables on the site: it also carries per-bale sales converted to per ton with an assumed bale weight, marked estimated: true. Drop those rows for an exact-sale-only analysis.

• report_week, scraped_date, updated — the Monday of the report week, the date HayWire collected it, and the build time.
• prices[] — the records. region is the USDA market (RockValley_IA_Mon), state and state_code its state, report_date the USDA report the line came from.
• commodity, quality, bale_type — alfalfa, grass, mixed and so on; the USDA grade (Supreme, Premium, Good, Fair, Utility; null when USDA stated none); the package as reported.
• price_low, price_high, price_avg, unit — US dollars per ton, as USDA printed the range.
• estimated, assumed_bale_lbs, original_unit, converted — estimated: true marks a per-ton price derived from a per-bale report using assumed_bale_lbs; the original per-bale price is price_avg × assumed_bale_lbs ÷ 2000.
• source, source_kind, source_url, sale_type — the publisher of the line (USDA AMS, or an auction house USDA does not cover) and the kind of sale.

Every record is an exact reported trade. There are no asking prices, no estimates and no interpolation anywhere in the file.

index.json, the HayWire Hay Index.

The index lives at haywireag.com/api/index.json: the weekly national hay price index in dollars per ton, plus one series per commodity. It is composition-stable: a week's move is computed only across markets that reported in both weeks, so a thin week never reads as a price move.

• latest_week, updated, revision — the newest complete report week, the build time, and the revision log of published values.
• national.latest, national.wow_pct, national.series — this week's level, its change from last week, and the full weekly history as [week, value] pairs.
• commodities — the same shape per commodity (alfalfa, grass, mixed).
• methodology, inclusion — the rules in words: exact per-ton trades only, the gates every published number passes.

Cite it as the HayWire Hay Index, with the week. The same number appears on the prices page, in the Tuesday Wire and in the Friday Pulse.

Free to cite, with attribution.

Quote any figure with "HayWire (haywireag.com)" and the report week. A link back is appreciated and not required. Reproducing the files, loading them into a product, or reselling the data is commercial use and needs a data license; write to haywireagprices@gmail.com.

Both files change in place as USDA reports post through the week, so a figure quoted on Tuesday can differ from the same week's figure read on Friday. The updated field says which build you read.

One index of everything here.

Every public page is listed in haywireag.com/llms.txt with a one-line description of what its numbers mean, including the state pages, the briefs and these two files. An assistant that reads it can answer "what is hay selling for in Kansas" from the page that holds that answer and its report date.