PALO ALTO, CA – North America, once home to a reported 1,000 printed circuit board shops, now has 329.

That’s the latest sum as totaled by industry analyst Harvey Miller. Miller, who publishes Fab-File, a directory tracking the domestic PWB industry, finds the 10 largest North American-based fabricators account for half the region’s revenue. The North American PWB market is estimated at $3 billion, Miller wrote.

The number of shops as of March 1 was 329 in the US and Canada, Miller found, down 4.9% from a year ago. In the US, the number of shops dropped by 16, to 293, over the past year. California, with 101 shops, remains the principal place of manufacture.

Given the number of recent acquisitions, including DDi’s purchase of Coretec, and the overlap of locations (both companies have shops in Toronto, for example), more closures are likely on the way.