We propose a framework for understanding recurrent historical episodes of vigorous economic expansion accompanied by extreme asset valuations, as exhibited by the U.S. in the 1990s. We interpret this phenomenon as a high-valuation equilibrium with a low effective cost of capital based on...

We construct a perpetual youth DSGE model with aggregate un- certainty in which there are dynamically complete markets and agents have Epstein-Zin preferences. We prove that, when endowments have a realistic hump-shaped age-profile, our model has three steady-state equilibria. One of these...