Built out cities? A new approach to measuring land use regulation

We introduce a new way to measure the stringency of housing regulation. Rather than a standard regulatory index or a single aspect of regulation like Floor Area Ratio, we draw on cities' self-reported estimates of their total zoned capacity for new housing. This measure, available to us as a result of state legislation in California, offers a more accurate way to assess local antipathy towards new housing, and also offers a window into how zoning interacts with existing buildout. We show, in regressions analyzing new housing permitting, that our measure has associations with new supply that are as large or larger than conventional, survey-based indexes of land use regulation. Moreover, unbuilt zoning capacity interacts with rent to predict housing production in ways conventional measures do not. Specifically, interacting our measure with rent captures the interplay of regulation and demand: modest deregulation in high-demand cities is associated with substantially more housing production than substantial deregulation in low-demand cities. These findings offer a more comprehensive explanation for the historically low levels of housing production in high cost metros.