This paper examines a stochastic endogenous growth model in which term
s-of-trade uncertainty affects savings and growth. The model explains
the well-known positive link between growth and the mean rate of chang
e of terms of trade,and predicts also that terms-of-trade variability
affects growth. Increased terms-of-trade variability results in faster
or slower growth depending on the degree of risk aversion, but in eit
her case it reduces social welfare. These growth effects imply that we
lfare costs of macroeconomic uncertainty are much larger than first th
ought. Cross-country panel regressions provide strong support for the
model's key predictions. (C) 1997 Elsevier Science B.V.