Bloomberg said that Ericsson AB, the world’s largest maker of wireless networks, reported fourth-quarter profit that missed analyst estimates as North American customers slowed spending and new upgrade contracts in Europe pared margins.

“In the fourth quarter we saw weaker development in networks, as well as an expected gross margin impact from a changed business mix with more coverage projects, modernization projects in Europe, and a higher services share,” Chief Executive Officer Hans Vestberg said in the statement.

The Stockholm based firm reported net attributable profit for the fourth quarter sank 65 percent to 1.49 billion Swedish kronor ($221 million) against a profit of 4.32 billion kronor in the year-earlier period.

The Ericsson stock dived almost 15 percent in opening trade, dragging down the OMX Stockholm index.