The number of cities that are getting too expensive is growing rapidly this year as prospective homebuyers cope with a limited supply of homes, according to a study.
“Of the top 100 real-estate markets in the U.S., 14 are now overvalued -- more than double the number that were at the end of the first quarter in 2015,” writes MarketWatch’s Catey Hill, citing a study by CoreLogic.

A city is considered overvalued if its home prices are expensive compared with average incomes of residents over the longer term.

"Just because you're overvalued doesn't mean that you're in a bubble or there is an impending crash. Some markets are overvalued because of strong fundamentals," Sam Khater, CoreLogic's deputy chief economist, tells Diana Olick at CNBC.

Six of the most expensive markets are in Texas, where strong job and income growth has boosted demand, even as the price of oil collapsed since mid-2014.

Austin, Texas, leads the list of overvalued housing with prices that are 42 percent above what CoreLogic considers sustainable. Home prices have risen more than 16 percent in the state capital since early 2014, according to MarketWatch.

Other expensive cities:

• Houston – 25.4 percent overvalued
• Charleston, S.C. – 23.4 percent
• Miami – 20.6 percent
• Washington – 19 percent
• Knoxville, Tenn. – 14.4 percent
• Philadelphia – 14.2 percent
• Dallas – 14 percent
• San Antonio – 12.4 percent
• Nashville, Tenn. – 12.3 percent

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