What explains Manhattan's declining share of residential construction?

Dense, expensive, litigious, and highly regulated, Manhattan typifies coastal US housing markets. Manhattan has lost share of US residential construction over the last 45 years. Some attribute this trend to tightening local regulation, but the decline of public housing construction and the decreasing national share of construction that is multifamily jointly explain away Manhattan's decline. Across US counties, negative correlations between supply growth and both coastal status and regulations disappear conditional on population density.