Kevin Erdmann offers a helpful corrective to the “YIMBY triumphalism” of claiming that large relative rent declines in Austin and Minneapolis are results of YIMBY policies. He’s mostly correct, especially about the rhetoric: arguing about housing supply from short term fluctuations is like arguing about climate change based on the week’s weather. Keep your powder dry, promise slow change and long-term stability, and recognize that demand shocks are responsible for most fluctuations.
But Erdmann makes a stronger claim:
Supply has never and will never cause a collapse of prices and rents. It causes stability.
Is that true? In a case like Austin or Phoenix, sure: prices are not too far above the cost of construction, and abundant supply cannot (durably) push the price of new housing below the cost of construction.
But YIMBY has more to offer to San Francisco, Auckland, or London. In those cases, prices are far above construction cost. That means that even when demand is relatively soft, there’s money to made in construction. As Erdmann allows:
After a decade of more active construction in Auckland, rents appear to be 10% to 15% below the pre-reform trend. That’s a big win. After a decade. That’s what success looks like.
That’s the promise – 5 to 15% relative rent declines, decade after decade. But there are several good reasons to believe this won’t happen in an even, steady pattern, at least not all the time. Hopefully by 2040 we’ll have data from several cases and be able to describe the dynamics of market restoration with much more confidence.