500. Calcutta North West

Indian National Congress held the seat; the winning margin widened from 12.7% to 19.1%.

Boundaries were redrawn between 1962 and 1967 — the comparison is matched by name and is indicative only.

• Won on a lower shareIts own vote share fell 8.9% — it held because the rest of the vote was more divided.
• New challengerIndependent (IND) finished second with 26.5% — it did not contest here in 1962.
• Vote fragmentedThe top two took only 72.2% between them, down from 96.4% — the field split more ways.
• TurnoutTurnout fell 6.2% to 57.3%.

Written from the constituency figures by a fixed set of rules — no language model.