And it was worse than I'd remembered when I composed the above; as Wikipedia says, "In Samuelson's 1973 edition of his famous textbook, he laid forth the prediction that the Soviet Union would catch up to the United States in per capita income by 1990, and almost certainly would by 2015 because of its superior economic system. Subsequent editions of his textbook would later push the date of his prediction back farther until the Soviet Union ultimately collapsed."