(FORTUNE Magazine) – Despite the collapse of Communism in the Soviet Union and Eastern Europe, Karl Marx's Das Kapital is selling at about the same rate in the U.S. as last year. Vintage Books, a division of Random House, says it sold 2,300 copies in 1989 and 1,700 through September. Today's Marx market is not exactly free. Most buyers are college students for whom the book (renamed Capital, $14.95 in paperback) is required reading. At Columbia, professor Allan Silver uses it for his course Political Sociology: Traditions and Concepts. - M.A.