BANNOCKBURN, IL – The September 90-day moving average shipments of all types of circuit boards rose 5.3% year-on-year, and bookings rose 36.7%, according to the latest poll of North American PCB fabricators.

A large percentage of the production includes boards built offshore and distributed by North American vendors. According to IPC, 29% of the shipments reported were produced offshore.

The domestic book-to-bill ratio rose to 1.18. 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 rose to 1.07, while that of flexible circuits rose to 1.52.

“PCB sales were up in September, following the typical seasonal pattern,” said IPC in a statement. “Compared to last year, rigid PCB sales are staying flat and flexible circuits are continuing their strong growth trend. September bookings numbers are way up in both segments of the industry, which is an encouraging sign for fourth-quarter business.”

Rigid board shipments, estimated by IPC to make up more than 75% of all domestic PCBs, were down 0.5% in September vs. a year ago. Bookings rose 20.2% during the month.

Flex sales rose 28% and bookings jumped 81.4%. Value-added services made up 83% of the shipment value of flex circuits.

Year-to-date, rigid shipments are down 4.7% and bookings are off 1.2%. Flex bookings are up 28.7% and shipments are up 27.4%. Shipments of all boards are up 1.2% and bookings are up 5.9%.

Sequentially, combined shipments were up 9.4% over June, while bookings were up 32.4%. Rigid shipments were up 11.1% and bookings were up 14.9%. Flex shipments fell 4.3% and bookings were up 84.5% over June.

Seventy-one percent of PCB shipments reported was domestically produced. Domestic production accounted for 84% of rigid PCB and 33% of flexible circuit shipments in July, IPC said.

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