NEENAH, WI – Electronics manufacturing services firm Plexus reported fourth-quarter net income was $18.3 million, a drop of 31.1% year-over-year.

The contract printed circuit board assembler said sales fell 3.15% compared to the fourth quarter of 2010 to $538.1 million.

In the quarter, the Industrial segment saw 21% growth sequentially, helped by Coca-Cola, although this was more than offset by declines in all other segments, particularly Networking and Wireless Infrastructure, which both dropped 17% on lower customer demand and program ramp downs.

On a conference call with analysts, Plexus said it expects first-quarter 2012 growth to be significantly lower than its long-term annual revenue goal of 15%, as a result of increased economic uncertainty. The firm sees continued volatility in customer forecasts.

Plexus expects first-quarter revenue of $510 million to $540 million, with all of its segments declining sequentially, except Networking/Communications.