Payment evidence study - private filled record. Question, observation period, time zone and cutoff: Definition of completed payment; refunds and failures: Providers, networks and assets included and omitted: Raw source, export/query, timestamp and checksum: Count, value, average size and distinct-user definitions: Duplicate/internal/bot/filter treatment: Conversion currency, exchange-rate source and timing: Methodology changes and missing coverage: For a route test: total customer outlay, fees, amount delivered, acceptance timing, bank payout and refund outcome: What this study can establish; what remains unmeasured: No private keys, credentials or customer personal data.