A key economic indicator increased more-than-expected in August, continuing momentum of an improving economic outlook.

Leading indicators increased 0.4 percent in August, greater than the 0.2 percent increase economists polled by Reuters anticipated. This is up from a gain of 0.3 percent in the prior month, according to the Conference Board.

"While the economic impact of recent hurricanes is not fully reflected in the leading indicators yet, the underlying trends suggest that the current solid pace of growth should continue in the near term," said Ataman Ozyildirim, Director of business cycles and growth research at the Conference Board.

The index is a closely followed indicator for how healthy the U.S. economy is. The Conference Board tracks 10 components, including manufacturers' new orders, stock prices and average weekly initial claims for unemployment insurance.

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