2000s in the music industry Inc.), who surpassed Wal-Mart to become the US’s largest music retailer in April 2008. Sector leaders include: Many hundreds more stores operate worldwide, often prominent only in particular countries or specialist genres. A third kind of operator never retails directly to the public, instead offering branded whitelabel stores and portals for organisations including bricks-and-mortar music stores, mobile telephony operators and ISPs. Some services which initially only offered streaming of tracks now also offer a-la-carte downloads, either through third parties (e.g. Spotify) or fully integrated (Deezer, Juno Digital, Rhapsody etc.). In 2009 "Rolling Stone" reported a price war between iTunes and
Dual-sector model the industrial wage. Given the profit maximization assumption, employment of labor within the industrial sector is given by the point where marginal product is equal to the rate of wages, i.e. OM. Since the wages in the capitalist sector depend on the earnings of the subsistence sector, capitalists would like to keep down productivity/wages in the subsistence sector, so that the capitalist sector may expand at a fixed wage. In the capitalist sector labor is employed up to the point where its marginal product equals wage, since a capitalist employer would be reducing his surplus if he paid labor more