Indicators Index Gains 0.2% in Sept.

In a sign the economy’s seven-year expansion won’t slacken soon, a key economic barometer rose in September, posing its fifth straight monthly increase.

The 0.2% rise in the Conference Board’s index of leading economic indicators, released Tuesday, shows the index rising to 104.5, matching analysts’ expectations. The index posted a similar increase for August.

The index is designed to forecast economic activity six to nine months in advance. Its continuing string of gains is a sign no halt appears imminent for the economic expansion, already the third-longest in U.S. history.

The historic 554-point drop in the Dow Jones industrial average on Oct. 27 left some analysts wondering whether the U.S. economy’s slow and steady expansion had been affected by the currency and market turmoil in Southeast Asia. But most economists now say that although the region’s devalued money may lead to fewer U.S. exports to the region, the effect on America’s economy is likely be slight.

Estimates of sales to the countries formerly known as tiger economies range from 4% to 9% of U.S. exports. Judging from the impact of the Mexican currency crisis in 1994, exports could fall by 2% or 3%, said Cynthia Latta, an economist at Standard & Poor’s DRI in Lexington, Mass.

“The U.S. economy is not doing badly, but the turmoil in Southeast Asia and some spillover to Latin America is going to hurt the profits of some American companies,” she said.

Since the stock market roiling of last week, few analysts believe the Federal Reserve Board would risk unsettling markets further by raising interest rates when its policymaking Federal Open Market Committee meets next week.

Over the six months through September, the Conference Board index increased 1.6%. During the same period, seven of the 10 leading economic indicators advanced.

The leading index is a signpost for changes in the economy’s direction. When the index changes course and holds that new heading for at least three straight months, indications are the economy is shifting gears.

The Conference Board, a private research group, said six of the 10 leading indicators rose in September, and that the most significant signs of expansion were in a decline in new weekly claims for unemployment benefits and a rise in the growth of the money supply. The most significant decline was new orders received by manufacturers.

The index was first calculated in the late 1960s. It is periodically fine-tuned. The most recent major change came last year, when the components were reshuffled.