Whatever improvement there was in the MBA's purchase index was fleeting, falling back in the July 10 week by a heavy 9.4 percent to 258.8. Difficult job conditions and difficult credit conditions continue to limit home buying despite falling prices and low rates. Rates have been lower but are falling again, at 5.05 percent for 30-year loans for a nearly 30 point drop in the week. Low rates fuel demand for refinancing where the index rose 18 percent in the week to 1,707. Next data on the housing sector will be the housing market index tomorrow.