New York (CNN Business) Americans are growing more concerned about the trade war, and that's bad news for the economy.

These concerns led the August index to log its largest monthly drop since December 2012. The data also undercut consensus forecasts, which came in at 89.8 points, and not the expected 92.1 points. The number is based on a monthly survey of 600 households and their assessment of financial conditions and the economy.

on China and allies over the past months, "act to increase uncertainty and diminish consumer spending at home," said Richard Curtin, chief economist of the Survey of Consumers. The trade tactics of President Donald Trump , which have included reversals and threats of future tariffson China and allies over the past months, "act to increase uncertainty and diminish consumer spending at home," said Richard Curtin, chief economist of the Survey of Consumers.

And trends like this aren't easily reversed, Curtin warned.

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