BANNOCKBURN, IL - The 90-day moving average shipments of all types of circuit boards slipped 4.5% year-on-year in April, according to the latest poll of U.S. PCB fabricators. Bookings fell 6.5%, as slackened demand for rigid boards more than offset gains in orders for flexible circuits.

A large percentage of the production includes boards built offshore and distributed by North American vendors. According to IPC, which takes the poll, 31% of the shipments reported were produced offshore, up one point from March.

The domestic book-to-bill ratio dropped 0.05 points to 1.0, breaking a streak of four straight months above 1.0. The ratio is based on data collected by IPC from rigid and flex producers and is calculated by dividing three months worth of orders by sales. A ratio over 1.0 is considered an indicator of rising demand.

The ratio for rigid PCBs was down 0.01 to 1.03, while that of flexible circuits dropped 0.20 points to 0.87.

Rigid board shipments, estimated by IPC to make up 75% of all domestic PCBs, were down 10% in April vs. a year ago. Bookings were down 4.5% for the month.

Flex sales fell 17.9% and bookings plummeted 12.8%. Value-added services made up 53% of the shipment value of flex circuits.

Year-to-date, rigid shipments are down 5.9% and bookings are off 4.8%. Flex bookings are down 5% and shipments are up 26.2%. Shipments of all boards are down 0.3% and bookings are down 4.8%.

Sequentially, combined shipments were down 13.0% over March, while bookings fell 11.7%. Rigid shipments were down 19.3% and bookings fell 18.2% sequentially. Flex shipments were up 14.3% and bookings were up 23.5% against March numbers.

Sixty-nine percent of PCB shipments reported were domestically produced. Domestic production accounted for 78% of rigid PCB and 40% of flexible circuit shipments in April, IPC said.

In a statement, IPC cautioned that month-to-month comparisons should be made with caution as they may reflect cyclical effects.