The Leading Economic Index was unchanged after rising 0.2 percent in May and 0.8 percent in April.
The index is essentially a comparison to economic conditions in 2004, which have been assigned a value of 100.
In June, declines in new building permits, fresh factory orders and stock prices were offset by gains in consumer expectations, initial claims for unemployment insurance "and other financial indicators," said Conference Board economist Ataman Ozyildirim.
"However, the leading economic indicator's six-month growth rate remains positive, suggesting the economy will continue expanding through the end of the year," Ozyildirim said.
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