Every number is extracted from the company's own XBRL filings and annual reports — profit and loss, balance sheet, cash flow, shareholding and Ind-AS 108 segment data — so you are reading what was filed, not a third party's re-typing of it.
Directly from companies' own regulatory filings — XBRL submissions to the exchanges and published annual reports — which are parsed and reconciled rather than re-keyed by hand.
Three years on the free plan, ten years on Alpha Plus, and the full available filed history on Alpha Pro — including segment-wise data where companies report it.