Managed prices are a more nefarious cause for serial correlation.

Under the new system, described as "managed prices," companies seeking to raise prices must request clearance from trade authorities, the Government said.

Another reference quotes a trade ministry official as saying there are "good managed prices and bad managed prices."

Referring to Fuji and Konica, another Japanese maker of film, the official is quoted as saying "managed prices by the two film manufacturers are unavoidable."