TY - JOUR AU - Aghion,Philippe AU - Stein,Jeremy C. TI - Growth vs. Margins: Destabilizing Consequences of Giving the Stock Market What it Wants JF - National Bureau of Economic Research Working Paper Series VL - No. 10999 PY - 2004 Y2 - December 2004 UR - http://www.nber.org/papers/w10999 L1 - http://www.nber.org/papers/w10999.pdf N1 - Author contact info: Philippe Aghion Department of Economics Harvard University 1805 Cambridge St Cambridge, MA 02138 Tel: 617/495-6675 Fax: 617/495-4341 E-Mail: paghion@fas.harvard.edu Jeremy C. Stein Department of Economics Harvard University Littauer 209 Cambridge, MA 02138 Tel: 617/496-6455 Fax: 617/496-7352 E-Mail: jeremy_stein@harvard.edu AB - We develop a multi-tasking model in which a firm can devote its efforts either to increasing sales growth, or to improving per-unit profit margins by, e.g., cutting costs. If the firm's manager is concerned with the current stock price, she will tend to favor the growth strategy at those times when the stock market is paying more attention to performance on the growth dimension. Conversely, it can be rational for the stock market to weight observed growth measures more heavily when it is known that the firm is following a growth strategy. This two-way feedback between firms' business strategies and the market's pricing rule can lead to purely intrinsic fluctuations in sales and output, creating excess volatility in these real variables even in the absence of any external source of shocks. ER -