Editing Openai/696a591f-d750-8006-8907-5e4de0290571 (section)

==== 5) “Because ~40% of units are price-controlled, leftover supply is ~33% more expensive… and anti-landlord gov causes lack of development” ====

Verdict: mixed numbers; the causal claims and the “33%” figure are unsupported.
* Share regulated: Rent stabilized is ~41.3% of occupied rentals (so “~40%” is roughly right if they mean stabilization). Rent Guidelines Board<ref>{{cite web|title=Rent Guidelines Board|url=https://rentguidelinesboard.cityofnewyork.us/wp-content/uploads/2025/05/2025-HSR.pdf|publisher=Rent Guidelines Board|access-date=2026-01-17}}</ref>
* “Leftover supply is ~33% more expensive”: I can’t substantiate this with NYC HVS, RGB, or academic work. It sounds like a back-of-envelope assertion. If a specific study exists, it needs to be named.

On development, NYC production is influenced by zoning, financing, labor/material costs, interest rates, tax incentives (e.g., 421-a changes), and permitting. The RGB’s stock-change reporting shows tax incentive programs (not rent regulation alone) have been major drivers of stabilized additions. Rent Guidelines Board<ref>{{cite web|title=Rent Guidelines Board|url=https://rentguidelinesboard.cityofnewyork.us/wp-content/uploads/2025/05/2025-Changes-Report.pdf|publisher=Rent Guidelines Board|access-date=2026-01-17}}</ref>
It’s reasonable to argue regulation affects investment incentives at the margin, but a clean claim “NYC gov isn’t friendly → therefore lack of development” is too monocausal and doesn’t match how housing supply is actually determined.

Also note: general economic literature finds some forms of rent control can reduce supply via conversions/withdrawals (e.g., the paper you cited even references that channel), but NYC-specific magnitudes are contested and not captured by a “33%” talking point. Kasey Zapatka<ref>{{cite web|title=Kasey Zapatka|url=https://www.kaseyzapatka.com/assets/pdf/affordable_regulation.pdf|publisher=Kasey Zapatka|access-date=2026-01-17}}</ref>