{
  "schema_version": "1.0.0",
  "dataset_id": "O005-LEGA-V101-CH05-DATA01",
  "unit_id": "O005-LEGA-V101-CH05",
  "filename": "popclockest.txt",
  "title": "Historical National Population Estimates: July 1, 1900 to July 1, 1999",
  "publisher": "Population Estimates Program, Population Division, U.S. Census Bureau",
  "source_url": "https://www2.census.gov/programs-surveys/popest/tables/1900-1980/national/totals/popclockest.txt",
  "source_relation": "The source URL is the official URL cited by Problem 16 of Pressbooks record 48.",
  "retrieved_at_utc": "2026-08-21T20:58:31Z",
  "http_status": 200,
  "response_content_type": "text/plain",
  "response_last_modified": "Wed, 24 Aug 2016 20:52:17 GMT",
  "bytes": 8148,
  "sha256": "f59dbd91b2bf975df7b7fb4af6de52dc3c68a705632e83d60410d98781206f09",
  "line_endings": "LF",
  "terminal_lf": true,
  "parser_contract": {
    "row_pattern": "^\\s*July 1,\\s+(\\d{4})\\s+([\\d,]+)",
    "expected_year_min": 1900,
    "expected_year_max": 1999,
    "expected_rows": 100
  },
  "source_notes": [
    "The source states that 1900–1949 exclude Alaska and Hawaii.",
    "The source states that 1940–1979 cover the resident population plus Armed Forces overseas; other years cover only the resident population.",
    "The source states that 1900–1929 values are rounded to the nearest thousand."
  ],
  "rights_note": "Official U.S. Census Bureau statistical data, redistributed verbatim for offline reproducibility with source attribution; no endorsement is implied. This project makes no broader rights claim for the source website.",
  "change_note": "No content changes; exact downloaded bytes are retained."
}