That was never such a "rule"; that was 1 of 4 considerations from a 1974 NY Times opinion piece, and those 4 considerations were in turn a simplification of the

That was never such a "rule"; that was 1 of 4 considerations from a 1974 NY Times opinion piece, and those 4 considerations were in turn a simplification of the overall recession considerations, as the combined 4 items were intended to be more understandable by the general public than the actual items. Where had you heard that there was such a "rule"? (And as others pointed out, it's a private organization, not the government, that has set and evaluates recession criteria.)