Nationally, the HOI was at 72.3 percent in the second quarter, unchanged from the same time period last year and close to the index's record-high 72.5 percent, set in first-quarter 2009.
The HOI tracks the share of homes sold in a particular area that would have been affordable to a family earning the local median income. The index assumes a family can afford to spend 28 percent of its gross monthly income on housing, according to NAHB's website.
