On average, Texas homes are now overvalued 10% to 15% after home prices grew faster than incomes in Dallas and Houston over the past two years, according to credit ratings agency Fitch Ratings.

According to Fitch’s February U.S. RMBS Sustainable Home Price Report, Dallas became overvalued in 2014 and Houston in 2013. Price growth rose for 42 and 54 consecutive months respectively in these cities. Over the past two years, increasing prices increased more rapidly than income growth by 3.3%.

In some cities, the declining prices of oil had an impact on the market as it pushed down drilling activity. This decline in income diminishes sustainable prices. The Baker Hughes oilrig count was down 42% in March from a year ago, and down 75% from November 2014.

The greatest potential for impact from the declining oil prices is in cities such as Midland, where the natural resources industry makes up about 40% of the income.

Houston faces less risk, with only 10% of wages originating from oil and gas, and Dallas is well diversified in around the private sector, outside of natural resources.