TY  - JOUR
AU  - Blanchard,Olivier
AU  - Rhee,Changyong
AU  - Summers,Lawrence
TI  - The Stock Market, Profit and Investment
JF  - National Bureau of Economic Research Working Paper Series
VL  - No. 3370
PY  - 1990
Y2  - May 1990
UR  - http://www.nber.org/papers/w3370
L1  - http://www.nber.org/papers/w3370.pdf
N1  - Author contact info:
Olivier J. Blanchard
International Monetary Fund
Economic Counsellor and Director
Research Department
700 19th Street, NW
Rm. 10-700
Washington DC, 20431
Tel: 202-623-7825
Fax: 202-623-7271
E-Mail: blanchar@mit.edu

Lawrence H. Summers
Harvard Kennedy School of Government
79 JFK Street
Cambridge, MA 02138
Tel: 617/495-9322
Fax: 617/495-0436
E-Mail: lhs@harvard.edu
AB  - Should managers, when making investment decisions, follow the signals given by the stock market even if those do not coincide with their own assessments of fundamental value? This paper reviews the theoretical arguments and examines the empirical evidence, constructing and using a new US time series of data on the q ratio from 1900 to 1988. We decompose q - - the ratio of the market value of corporate capital to its replacement cost - - into the product of two terms, reflecting "fundamentals" and "valuation", the ratio of market value to fundamentals. We then examine the relation of investment to each of the two, using a number of alternative proxies for fundamentals. We interpret our results as pointing, strongly but not overwhelmingly, to a larger role of "fundamentals" than of "valuation" in investment decisions. 
ER  -