By force of demand

"This paper shows that economic fluctuations can be largely demand-driven. In particular, the stylized open-economy business cycle regularities documented by Feldstein and Horioka (1980) and Backus, Kehoe and Kydland (JPE 1992) can be explained by the standard general equilibrium theory if consumption demand is treated as the primary source of aggregate uncertainty. Frictions such as market incompleteness, increasing returns to scale, and sticky prices are not needed for resolving these longstanding puzzles"--Federal Reserve Bank of St. Louis web site.