There are increasingly urgent voices counselling that it’s all going to end in tears, but the boom in demand for chips shows no signs of flagging yet, and the US Semiconductor Industry Association reported an April book-to-bill figure of 1.19, up from 1.17 in March and February. Most noteworthy was that average monthly orders for the three months to end-April hit a four-year high of $1,210m, the highest since the figure for the three-month period to May 1984. Shipments of computer chips to the US market in April came to $993.9m, down 8% on the figure for March, but up nearly 27% on the April 1987 figure. Average monthly shipments for the three months to April were $1,000m, while average monthly orders for the three months to April were $1,210m, 7.8% up on the March figure. The Association says that the boom is broadly-based, covering both memory and logic chips. It still reckons that business will be over 25% up on 1987 this year.