Some dump files carry a trailing 'ctime' column: an older pipeline
appended a FULL re-download of the symbol per download (up to ~28
vintages per date, 2019-2022). The consumer keeps the last row per date,
so it silently used stale (~2021) vintages where Yahoo later revised
values. scripts/clean_multivintage.py keeps, per date, the rows from the
newest ctime (event files keep distinct same-day amounts; history/split
keep the single newest row), drops the ctime column, sorts by date.
Applied to the data root and overrides/frozen (which carried the same
artifact): 1,065 files, 2,202,712 stale rows dropped.
Also: stripped 3 UTF-8 BOMs (teg/lo/krft), refreshed the event backup
with the cleaned files, and re-ran the double-listing scan: category C
(83 symbols, 18,636 repeated within-file rows) is fully explained by the
multi-vintage artifact and is now gone; A (6,589 pairs, corrected) and
B (12,366 pairs, open review list) are unchanged. Whole-set structural
QC after cleaning: 0 duplicate dates, 3 syms/15 rows of OHLC invariant
violations, 15 syms/2,897 rows of non-positive prices (mostly
long-delisted tickers), 8 unsorted files (reader sorts).
230 tickers whose Yahoo chart responses now come back without a timestamp
array (terminated/merged funds): goget overwrites the .json on every pass
while ohlc.Conv skips the write, leaving the old CSVs as the last known
series. Snapshot them into overrides/frozen/ (git-tracked, audited in
reports/stale-funds.md) and make data.py prefer the frozen copies and
ignore any future data-root rewrite/delete for those symbols, so the
final series survives future goget runs. The cache manifest now covers
the overrides dir too; incremental refresh skips data-root files of
frozen symbols.
