If only the Federal Reserve had hiked rates in response to the boom in house prices, the U.S. could have avoided the housing bubble that caused the Great Recession.

At least that’s the argument, but it’s one a new San Francisco Fed study dismisses in an article published Monday.

A research article by San Francisco Fed economist Oscar Jorda, University of Bonn professor Moritz Schularick and University of California Davis professor Alan Taylor examined just how high interest rates would have had to have been to keep house prices on trend.

Using data going back to 1870 and covering 16 advanced economies, they quantify the responsiveness of mortgage lending and house prices to interest rates. For every one percentage point increase in rates, they find, the accumulated decline in house prices is about 4.4% after four years.

The problem was that by 2006, prices were about 40% above trend. In other words, to keep a lid on prices, there would have needed to be an 8 percentage point increase in the federal funds rate back in 2002.

Such a large rate rise would have depressed output more than the Great Recession did, the economists found.

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What actually happened was the Fed funds rate stayed between 1% and 1.25% from the end of 2002 to the middle of 2004, and then started rising to 5.25% by June 2006.

Taken to its logical extension, the San Francisco Fed paper pushes back on the idea the central bank really can restrain asset prices, at least through rate policy.

“Slowing down a boom in house prices is likely to require a considerable increase in interest rates, probably by an amount that would be widely at odds with the dual mandate of full employment and price stability. Moreover, the Fed would need a crystal ball to foretell house-price booms. In restraining asset prices, while the power of interest-rate policy is uncontestable, its wisdom is debatable,” the economists wrote.

They do allow that, perhaps, the Fed could have merely brought house-price growth down, and not to the trend, therefore requiring only a smaller rate hike. Alternatively, they suggest the Fed could have triggered a recession with a rate hike smaller than eight points, and that could have slowed house prices more than they calculated.

The study comes at a sensitive time for Fed interest-rate policy, with some anticipating the central bank may make its first rate hike since 2006 in September.