The 99+% accuracy standard applies to every file, and it holds because each translation is produced by a person and then checked against the source by a second reviewer. Dates, figures and proper nouns are checked separately from the prose, because those are the details a reviewing office compares first. What gets checked on reliable translation is the detail a reader would otherwise have to verify alone: names, figures, terms and anything the source left ambiguous. Anything genuinely unclear is flagged for you, never guessed at.