The Chicago Federal Reserve Bank's monthly National Activity Index fell to a reading of minus 0.04 in August from 0.08 in July, as expected in a survey compiled by Bloomberg.
The three-month moving average rose to 0.01 from minus 0.01.
Of the 85 individual indicators, 39 made positive contributions to the index in August, while 46 made negative contributions. Some 34 indicators improved in the month, while 49 indicators deteriorated and two were unchanged.