Consumer confidence rose in September, notching its highest level in about 18 years.

The Conference Board's index rose to 138.4 this month from 134.7 in August. Economists polled by Reuters expected consumer confidence to dip to 132.

"Consumers' assessment of current conditions remains extremely favorable, bolstered by a strong economy and robust job growth," said said Lynn Franco, director of economic indicators at the Conference Board. "These historically high confidence levels should continue to support healthy consumer spending, and should be welcome news for retailers as they begin gearing up for the holiday season."

Franco added September's index print is near the all-time high of 144.7 reached in 2000.

The survey measures Americans' sentiment on current economic conditions and prospects for the next six months, including business and labor market conditions.

The Conference Board also said optimism about the short-term outlook improved considerably this month, with 27.6 percent of consumers expecting business conditions to improve over the next six months; that's up from 24.4 percent in August. Consumers expecting business conditions to worsen, meanwhile, dropped to 8 percent from 9.9 percent.

Labor-market expectations also improved in September as 22.5 percent of consumers expected more jobs in the months ahead, up from 21.5 percent in August. This comes after the Labor Department said Thursday initial weekly jobless claims fell to their lowest level in nearly 49 years, totaling 201,000 for the week ending Sept. 15.

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