# Data provenance — F1-conf-01

All three files concern the same series: **CPIAUCSL**, Consumer Price Index for All Urban Consumers: All Items in U.S. City Average, seasonally adjusted, index 1982–1984 = 100, monthly, produced by the U.S. Bureau of Labor Statistics and distributed by the Federal Reserve Bank of St. Louis (FRED / ALFRED). Terms: FRED/ALFRED terms of use (BLS data are in the public domain; attribution to BLS and FRED requested). Observed data, not simulated.

| file | content | source URL | retrieved (UTC) | SHA-256 of the raw download |
|---|---|---|---|---|
| `cpi_vintage_2016-07-15.csv` | vintage of 2016-07-15 (values as published on that date), months 1947-01 … 2016-06, 834 rows | https://alfred.stlouisfed.org/graph/alfredgraph.csv?id=CPIAUCSL&vintage_date=2016-07-15 | 2026-10-30T03:22Z | 74c7c4e0e3fa26059421d9620abe12d57df9a7786012acf39d694766cb854f6d |
| `cpi_vintage_2026-10-28.csv` | vintage of 2026-10-28 (latest), extract restricted to months 2014-01 … 2026-09, 153 rows | https://alfred.stlouisfed.org/graph/alfredgraph.csv?id=CPIAUCSL&vintage_date=2026-10-28&cosd=2014-01-01 | 2026-10-30T03:24Z | 480c9f9931a48e3194b73a8f6b65b325a51e185232456c1222a260dde64f9730 |
| `cpi_assembled.csv` | a single monthly file assembled by the task author from the two extracts above, intended to cover 1947-01 … 2026-09 with a `vintage` column recording which extract each value came from | assembled from the two files above | 2026-10-30 | — |

Columns of the vintage files: `date` (first day of the month, ISO), `cpi` (index level, 3 decimals). The assembled file adds `vintage` (the vintage date of the extract the value was taken from). The raw downloads were reformatted (two columns, ISO dates) without changing any value. An empty `cpi` cell means the source publishes no value for that month. The assembled file was produced by hand and may contain assembly errors.