US manufacturers saw a great rise in expansion this last month but the forecast on the price of raw materials may put a kink in the production line.

WASHINGTON –  U.S. manufacturers expanded at the fastest pace in nearly seven years last month, but a sudden rise in the price of raw materials could threaten their profits.

The Institute for Supply Management said Tuesday that its index of manufacturing activity rose to 61.4 in February, up from 60.8 the previous month. That's the highest reading since it reached the same level in May 2004. The ISM's index bottomed out at 33.3 in December 2008, its lowest point in nearly 30 years.

Any reading above 50 indicates expansion. The manufacturing sector has now expanded for the past 19 months.