To confidentialise, estimates in this data cube have been rounded to the nearest 10. As a result, sums of the components may not add exactly to totals. Rounded figures and unrounded figures should not be assumed to be accurate to the last digit shown. Analysis featured in the publication is based on unrounded data.
Both round() and signif() round numbers to the nearest possibility. If the first digit that is dropped is exactly 5, R uses a rule that's common in programming languages: Always round to the nearest even number. round(1.5) and round(2.5) both return 2, for example, and round(-4.5) returns -4.
Remember, we did not necessarily round up or down, but to the ten that is nearest to 664. First, 664 rounded to the nearest ten is: 660. When rounding to the nearest ten, like we did with 664 above, we use the following rules: A) We round the number up to the nearest ten if the last digit in the number is 5, 6, 7, 8, or 9.