lacuna

DECLARED COVERAGE BLIND SPOT

written by a person · artifact 2026-07-27/v2-bridge-k5 · SHA-256 73847f8ff535e7d2…

Literature before about 1970 thins out sharply

Measured on 2026-07-27: OpenAlex holds roughly 1.38M works published in 1980, 1.05M in 1970, but only 305K in 1950 — about a fifth of the 1980 density. Historical analyses become progressively less trustworthy the further back they reach, and an apparent gap in older literature may simply be an unindexed one.

coverage severity
partial

MEASURED CONTEXT

works 1980
1,383,251
works 1970
1,051,187
works 1950
304,575

This is a sourced, human-curated entry or a declared project limitation. It is not a computed discovery or an actionable hypothesis.

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