I find that most people don’t have original opinions.
This phenomenon has gotten much worse since the launch of ChatGPT. We imbibe and regurgitate a cocktail of thoughts from LLMs, our Twitter feeds, the news, and politicians.
I say “we” here because I catch myself doing this, too. This post is a step in the opposite direction.
In the NYC Mayoral Election of 2025, Zohran Mamdani proposed rent stabilization policies to combat the city’s housing affordability crisis. As an NYC resident for three years, I can attest that rent is expensive, and I appreciate the principles and charisma Zohran brought to the mayoral race.
However, I don’t want to parrot politicians’ positions without doing my own research first, so I did some digging.
From a review of academic literature, New York does suffer from a housing supply shortage. New units (“housing starts”) can’t keep up with rising demand and migration into the city. The city suffers from “inelastic housing supply”, i.e. housing supply does not respond sufficiently to increases in price.1 Schwartz, A. (2019): New York City’s Affordable Housing Plans and the Limits of Local Initiative,2 “Glaeser, E. L., Gyourko, J., & Saks, R. E. (2005). Why Have Housing Prices Gone Up?”
In the 2010 Quarterly Journal of Economics we can see NYC’s supply elasticity issues when compared to other US cities:3 Saiz 2010
| City | Supply Elasticity | Rank (out of 95) |
|---|---|---|
| New York, NY | 0.76 | 9 |
| Chicago, IL | 0.81 | 12 |
| Houston, TX | 1.99 | 67 |
| Atlanta, GA | 2.21 | 74 |
It doesn’t look much better today; in 2023, the city’s vacancy rate for housing was 1.41%, its lowest in 50 years.4 NYC Rent Guidelines Board: 2025 Housing Supply Report For reference, a healthy “natural” vacancy rate in the rental market is estimated to be between 5-10% and peer cities (DC, LA, SF) have vacancy rates of 5+%.5 Study by Harvard Joint Center for Housing Studies. See also individual data for DC, SF, LA.
But why is this the case? Landlords might blame the city’s pro-regulation swing since 2019 (like the Housing Stability and Tenant Protection Act), but I don’t find that argument convincing. Although there was a spike in vacant / warehoused / dilapidated units after the law was enacted, COVID was a significant confounding factor. By March 2024, only < 0.2% of the rent-controlled stock was uneconomical to renovate, and only 2.7% of units were vacant that would qualify for rent stabilization.
An argument that I find more convincing is that NYC’s housing shortage is a symptom of what Ed Glaeser calls the “closing of the American urban frontier”. Through most of the 20th century, Americans moved from poorer places to richer places because they could enrich themselves doing so (and could find affordable housing!). This was most noticeable with Black Americans, especially with the Great Migration from the Jim Crow South, but the same patterns held even for White Americans. From ~1900-1990, more than 6% of Americans moved across counties each year.6 “Glaeser 2020: The Closing of America’s Urban Frontier”. Fun fact: Glaeser taught a microeconomics class that I took in college which I still remember fondly. He is a remarkably warm and intelligent person, and I hope you have the pleasure of meeting him too, someday!
This pattern has slowed down significantly, particularly for cities like New York. First, NYC is a much older city than Atlanta or Houston and is not built around the highway and car. Thus, despite attempts to retrofit highways to the city, it is much more difficult for residents to live on the outskirts and commute in via automobile. Builders can’t just expand on the outskirts to supply new housing. Second, builders like Robert Moses (of Power Broker fame) were increasingly stopped after the 60s by activists like Shirley Hayes and Jane Jacobs, who fought to landmark places like Washington Square Park. Broadly speaking, local groups have become more politically powerful as they lobby against new construction with (many legitimate) concerns: new construction devalues their property and can change the quality of their neighborhoods (e.g. destroying city landmarks!).
In other words, new construction can be surprisingly politically difficult.
Rent control (as a price-fixing scheme) has a depressive effect on housing construction, which is the opposite of what New York needs. A few ideas that seem more promising:
All of this said: I am glad that politicians in the city are drawing attention to the housing crisis. But given that NYC:
I am suspicious of rent control as anything but a convenient political scheme. I am certain I missed key facts here, but I tried to be as unbiased as possible when conducting research. If you have any addendums or thoughts, please do get in touch — I would love to know how I am wrong about this!