December 30, 2010 1:10 PM, EST

Chicago Manufacturing Index Improves

Manufacturing activity in the Chicago region jumped this month, indicating overall strength in the U.S. economy, the Institute for Supply Chain Management-Chicago said Thursday.

ISM-Chicago’s monthly index rose to a reading of 68.6, from 62.5 in November. Figures greater than 50 signal expansion.

The reading was better than economists’ median estimate of a decline to 61, Bloomberg reported.

Chicago is a major center of U.S. manufacturing, which is one of trucking’s largest and most important customers.