German factory orders in September dropped deeply, according to figures released Monday by the Ministry for Economics and Technology.

The data showed that factory orders slumped by 2.5 percent over that in August, when the figure surged 3.7 percent. Experts expected a decline of 0.9 percent in September in orders, which have been regarded as a key volatile economic indicator.

Foreign orders led the fall as they dipped 6.2 percent, while domestic orders rose by 1.5 percent, the ministry said.

Export have been the main driving force for Germany's economy growth.