What actually happened
The place added homes, demand changed, and rents followed their observed path.
The comparison that matters
Compared with what?
A rent can rise after new housing opens and still be lower than it would have been without those homes.
Housing cost
No-building path
With more homes
The benefitLower than the alternative
Time →Housing outcomes reflect supply and demand at the same time. A growing job center may add thousands of homes while attracting even more households. Looking only at whether rents rose after construction mistakes a busy market for evidence that construction caused the increase.
What otherwise would have happened
Estimate the same place without the added supply while holding other forces as comparable as possible.
The difference between paths
The policy effect is observed housing cost minus the credible no-reform path.
A simple example
A growing city
Rents rise 8% while housing is blocked.
Rents rise 3% when added homes absorb part of the demand.
The new homes did not make rent cheap. They made it cheaper than continued scarcity.
See the evidence
Strong evidenceMore homes give renters more leverage.Read the studies →Established evidenceScarcity turns neighbors into bidders.Read the studies →