The EMS industry has posted several straight months of what some consider excessively high book-to-bill ratios. The April peak of 1.62 has only marginally fallen over the past couple months and, as of this writing, was 1.48 in June, the most recent data available.

As a refresher, the ratio is calculated by dividing the amount (in dollars) of bookings by the amount in shipments. In other words, if over a set time period a company gets $110 worth of orders and ships $100 worth of product, its book-to-bill ratio would be 1.10. A ratio over 1.0 is considered an indicator of future market growth.

So a positive ratio is a good sign, generally speaking, but too much of a good thing makes folks nervous. And ratios in the 1.40 and above range are historically at the high end.

Some are concerned of an overheated market, but conversations with several leading EMS firms suggest instead that OEMs are offering longer forecasts, which are inflating the numerator. For instance, if the typical window was six months, it might be nine or even 12 months now. That pushes more “orders” into the data pile, but it’s a mathematical anomaly, not a sign of double-booking.

I don’t expect the sky to fall, at least this time.