Buying a home is more affordable than renting one in 66 percent of housing markets in the U.S., with Cook County, Ill., Maricopa County, Ariz. and Miami-Dade County, Fla. among those with the highest buy affordability, according to ATTOM Data Solutions' 2017 Rental Affordability Report. Renting a home, to compare, is more affordable than buying one in 34 percent of markets, with Dallas County, Texas, Kings County, N.Y. and Santa Clara County, Calif. among those with the highest rent affordability. 

Predominantly impacting affordability are stagnant wages, which have lagged at a growth rate of 2.2 percent since one year ago, compared to home prices, up 5.7 percent, and rents, up 4.2 percent.  

Rising mortgage rates could deal another blow to affordability. Average rates, which retreated since charging forward following the election, are currently above 4 percent.   

Home price growth outpaced wage growth in 79 percent of the counties analyzed in the report, while rent growth outpaced wage growth in 62 percent. Wage growth, however, outpaced home price growth in 21 percent of the counties analyzed, and outpaced rent growth in 38 percent.  

A monthly house payment on a median-priced home will require 36.6 percent of average wages, according to the report; a monthly fair market rent will require 38.6 percent.