The average rate on a 30-year fixed-mortgage inched higher by 2bps from the previous week to 6.53% on the last week of May, according to data compiled by Freddie Mac. It was the highest level in nine months. The jump took place despite the pullback in long-term Treasury yields over the period as signs of progress between the US and Iran in their conflict trimmed soaring inflation concerns, although benchmark borrowing costs remained high.