The absence of a trend in hours worked in the postwar United States is an exception: across countries and historically, hours fall steadily by a little below 0.5% per year. Are steadily falling hours consistent with a stable utility function over consumption and leisure under balanced growth of the macroeconomic aggregates? Yes. We fully characterize the class of such functions and thus generalize the well-known “balanced-growth preferences” that demand constant (as opposed to falling) long-run hours. Key to falling hours is an income effect (of steady productivity growth on hours) that slightly outweighs the substitution effect.

Growth has fallen in the U.S. amid a rise in firm concentration. Market share has shifted to low labour share firms, while within-firm labour shares have actually risen. We propose a theory linking these trends in which the driving force is falling overhead costs of spanning multiple products or a rising efficiency advantage of large firms. In response, the most efficient firms (with higher markups) spread into new product lines, thereby increasing concentration and generating a temporary burst of growth. Eventually, due to greater competition from efficient firms, within-firm markups and incentives to innovate fall. Thus our simple model can generate qualitative patterns in line with the observed trends.