Source: Sam Khater/CoreLogic
Khater compared the share of million-dollar home sales to the S&P 500 and found a distinct correlation. While the share of $1 million or more homes is very small, just 1.2 percent of all home sales historically, it can move dramatically depending on stock market gains or losses. From the worst of the financial crisis in 2008 to the peak of the equity markets in May 2015, the share of million dollar and more home sales nearly doubled, according to Khater.
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"Since its peak in May 2015, the S&P index declined 10 percent as of mid-February. This decline in the S&P index was matched by a 30 basis point or 15 percent decline in the $1 million or more share," Khater said.
The correlation, however, is far more acute in certain locations.
In New York City and San Francisco, where the local economies are tied most to financial markets, sales of high-end homes have weakened, and supply is rising. That jump in inventory will likely affect prices down the road, as supply outstrips demand. Nationally there was a 9.3-month supply of homes listed at $1 million or above in December 2014, but that increased to 13 months by December 2015, according to CoreLogic.
"With more than a year's supply of inventory, prices, for the most part, won't be increasing," Khater said.
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In Washington, D.C., however, the stock effect is far more muted. Government, and the high-priced lawyers and lobbyists that surround it, are a steady denominator.