The index, which rose 0.6 percent from July, also received positive contributions from new unemployment claims and factory orders, which offset a slide in residential building permits.
The index, which assigns 2004 a base value of 100 for comparisons, rose to 116.3 in August, the Conference Board said.
The board said the index increased 1.5 percent over six months, slightly faster than the 1.2 percent average increase of the previous six months.
Police: Sword-wielding man demanded free tacos
Campus cop fatally shoots Texas student during traffic stop