Payments come from the corporate-actions record rather than from the filings. The XBRL tag for dividends covers only about a fifth of filers and arrives in a zoo of units, so the actual per-share cash — dated, with one-off specials flagged — is the more reliable source. The filings still answer whether earnings cover the payment.

The annual figure is the last 12 regular payments, not a rolling 365 days. A year-long window catches three payments or five depending on where its boundary lands — Exxon’s misses an August ex-date by two days and understates the yield by a quarter — so the count is what is summed, and a partial set publishes nothing rather than a low number.