"It's pretty much a story of falling energy prices," says Cheryl Abbot, a regional economist for the U.S. Bureau of Labor Statistics, based in Dallas. "For the two-month period, they were down by 3.4 percent in Houston, but over the year, they dropped by slightly more than 22 percent."
By contrast, Houston's core inflation rate, which factors out volatile energy and food prices, came to 2.8 percent for the year ending in August, slightly above the core rate for the U.S. as a whole.
"And the main reason there is that your shelter prices are increasing at a somewhat faster rate than the national average," Abbot says.
In terms of the CPI, "shelter" is a measure either of rents or what homeowners would have to pay in rents if they did not own their homes. The cost of shelter rose an average of 5.1 percent for Greater Houston between August 2014 and last month.