For the questions people actually bring - how a company was covered over years, what was reported before a market event, how coverage of a sector changed - the public record of headlines, standfirsts, bylines, sections and timestamps is the backbone. Collected on a schedule, it shows what the Journal chose to report and when.
Corrections add a second layer. Keeping the first published version and the corrected one side by side makes the gap between them measurable, which is a finding in itself for anyone studying financial journalism.
Influence is the third question: which Journal stories other newsrooms picked up and how quickly. Citation records answer it from the outlets doing the citing.