日前，IPC电子工业连接委员会月PCB统计项目组发布其3月份的PCB统计数据。 Industry Growth Rigid PCB shipments are down 12.6 percent and bookings are down 23.7 percent in March 2007 from March 2006.Year to date, rigid PCB shipments are down 9.0 percent and bookings are down 20.8 percent.Compared to the previous month, rigid PCB shipments increased 9.3 percent and rigid bookings increased 6.4 percent. PCB订单交货比 Flexible circuit shipments in March 2007 were down 1.6 percent and bookings were up 41.7 percent compared to March 2006.Year to date, flexible circuit shipments are up 4.2 percent and bookings are up 21.4 percent.Compared to the previous month, flexible circuit shipments increased 25.8 percent and flex bookings were up 111.4 percent. 北美刚性PCB订单交货比2007年3月升为0.99，柔性PCB则飙升至1。18。得益与此，2007年3月综合PCB（包括刚性和柔性PCB）订单交货比达到1.00。这个比值来源于参与IPC月PCB统计项目的PCB生产商。分析家指出，单独对刚性和柔性PCB统计订单交货比要比综合统计这一比值有意义，因为近年来刚性PCB和柔性PCB在增长速度和订单交货模式方面都有较大分别。 For rigid PCBs and flexible circuits combined, industry shipments in March 2007 decreased 11.9 percent from March 2006, and orders booked decreased 19.9 percent from March 2006.Year to date, combined industry shipments are down 8.2 percent and bookings are down 18.7 percent.Compared to the previous month, combined industry shipments for March 2007 are up 10.3 percent and bookings are up 12.3 percent. Rigid PCB sales continued to grow in March, despite lower sales compared to last year, said IPC President Denny McGuirk.In flexible circuits, the continued decline in sales reflects a normal seasonal pattern, he continued.The book-to-bill ratio for all PCBs has once again reached parity after declining in late 2006. This reflects overall stability despite slower growth in the first quarter of 2007, McGuirk added. The ratios are calculated by dividing the value of orders booked over the past three months by the value of sales billed during the same period from the companies in IPCs survey sample.A ratio of more than 1.00 suggests that current demand is ahead of supply, which indicates probable near-term growth. The book-to-bill ratios and growth rates for rigid PCBs and flexible circuits combined are heavily affected by the rigid PCB segment.Rigid PCBs represent an estimated 85 percent of the current PCB market in North America, according to IPCs World PCB Production and Laminate Market Report for the Year 2005. The Role of Domestic Production IPCs monthly survey of the North American PCB industry tracks bookings and shipments from U.S. and Canadian facilities, which provide indicators of regional demand.These numbers do not measure U.S. and Canadian PCB production.To track regional production trends, IPC asks survey participants for the percent of their reported shipments that were produced domestically (i.e., in the USA or Canada.)In March 2007, 89 percent of total PCB shipments reported were domestically produced.Domestic production accounted for 89 percent of rigid PCB and 95 percent of flexible circuit shipments in March by IPCs survey participants.These numbers are significantly affected by the mix of companies in IPCs survey sample, which remains constant throughout each calendar year, but may change with the January survey results. Bare Circuits Versus Assembly Flexible circuit sales typically include value-added services such as assembly, in addition to the bare flex circuits.In March, the flexible circuit manufacturers in IPCs survey sample indicated that bare circuits accounted for about 80 percent of their shipment value reported for the month.Assembly and other services make up a large and growing segment of flexible circuit producers business.This figure is also sensitive to changes in the survey sample, which may occur at the beginning of each calendar year. Interpreting the Data Year-on-year and year-to-date growth rates provide the most meaningful view of industry growth.Month-to-month comparisons should be made with caution as they may reflect cyclical effects.Because bookings tend to be more volatile than shipments, changes in the book-to-bill ratios from month-to-month may not be significant unless a trend of three consecutive months or more is apparent.It is also important to consider changes in bookings and shipments to understand what is driving changes in the book-to-bill ratio. The information in IPCs monthly PCB industry statistics is based on data provided by a representative sample of both rigid and flexible PCB manufacturers in the USA and Canada.IPC publishes the PCB Book-to-Bill Ratio and the Interconnect Manufacturing Services (IMS) Business Report each month.Statistics for the previous month are not available until the last week of the following month.