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No abstract

In the U.S., large firms now account for a greater share of economic activity, new firms are being created at slower rates, and workers are receiving a smaller share of GDP. Changes in population growth provide a unified quantitative explanation. A decrease in population growth lowers firm entry rates, shifting the firm‐age distribution toward older firms. Firm aging accounts for (i) the concentration of employment in large firms, (ii) and trends in average firm size and exit rates, key determinants of firm entry rates. Feedback effects from firm demographics generate two‐thirds of the effect. Prior to the decrease, entry rates rose steadily reflecting the earlier baby boom. The glut of firms due to the baby boom lead to rich transitional dynamics within the feedback effects, accounting for more than half the total change. Baby boom induced changes in the firm‐age distribution provide a driving force for the post‐WWII rise and fall in the aggregate labor share. Ignoring changes in population growth attributes all the long run decline in entry rates to a decrease in firm exit rates, which in reality have been only one‐third as large.

We study optimal tax policies in a life-cycle economy with permanent ability differences and risky human capital investments that have both an unobservable component, learning effort, and an observable component, schooling. The optimal policies balance redistribution across agents, insurance against human capital shocks, and incentives to learn and work. In the optimum, (i ) high-ability agents face risky consumption while low-ability agents are insured; (ii ) the optimal schooling subsidy is substantial but less than 100 percent; (iii) if utility is separable in labor and learning effort, the inverse labor wedge follows a random walk; and (iv ) if the utility is not separable then the “no distortion at the top” result does not apply. The welfare gains from switching to the optimal tax system are about 1 percent in annual consumption equivalents. (JEL D15, H21, H24, I26, J24)

For a sample of OECD countries, I document a systematic positive relationship between i) aggregate productivity, ii) the employment share by large firms and iii) the proportion of large firms in the economy. I propose that differences in bankruptcy procedures can explain this relationship. In a model of financial intermediation and informational frictions, I show that as bankruptcy procedures worsen -measured by the amount a lender can recover from bankrupt borrowers -lenders respond by i) shifting their portfolio of loans to smaller (less productive) firms and ii) lending less. This finding is supported by empirical evidence: across countries, efficient bankruptcy procedures are associated with a higher proportion of new bank loans allocated to large firms. In the model, moving the level of recovery rate from the U.S. level to that of the lowest recovery rate country in the OECD sample reduces TFP by around 30 percent.