A closely watched gauge of future economic activity rose sharply in January, suggesting the nation's economy could see robust growth in the spring, a private research group said Tuesday.

The Conference Board said its Index of Leading Economic Indicators, a measure of the economy's well-being in the near term, rose 1.1 percent last month. January's increase follows a 0.3 percent gain in December.

The leading index's January increase reflects improvement in six of 10 components, including stock prices and building permits. The index has increased 2.3 percent from July 2005 to January 2006.

In addition to the gain in the group's leading index, its coincident index, a measure of the current economy, rose 0.2 percent in January, following a 0.2 percent increase in December.

"The coincident economic indicators have been rising moderately but steadily in recent months, suggesting the economy is sustaining a relatively moderate pace," Ken Goldstein, the Conference Board's labor economist, said in a statement accompanying the data.

Goldstein added: "The Leading Economic Index, however, rose sharply in three of the last four months. That could be a signal of a faster pace this spring."