Interest Calculation & Posting — impact tolerance ≤ 1 business day — ITOL

Impact tolerance: ≤ 1 business day — any outage extending past the nightly batch posting cycle, for any share of accounts (illustrative default — trace the derivation, then replace with your own harm analysis)

Definition: Systematic calculation and periodic posting of interest earned on deposits or charged on loans, including Annual Percentage Yield (APY) computation and disclosure.

Why it is designated: Regulation DD (Truth in Savings) imposes strict rounding and accuracy rules on APY and interest-rate calculation and disclosure. A missed posting cycle risks disclosures that fail that accuracy standard once postings resume, so recovery is bounded to the next business-day cycle.