A book-to-bill ratio of 1.07 has been reported by the US Semiconductor Industry Association, which has revised the September and October figures to show 1.07 also. The Association reports that US ships in November rose 5% to $920m, while the average monthly orders for the three months to November 30 were up 1.6% at $997.1m, 110.5% above the cyclical low of $473.7m set in September 1985.This consistency in the ratio shows the steady growth of the semiconductor market, said Doug Andrey, the Association’s manager of Industry Statistical Programmes. Furthermore, November’s book-to-bill ratio is the twelfth in a row to be above parity, making one full year of positive ratios; this has not been seen since the 1983-84 boom. The ratio’s 13-month sequence from November 1986 is 0.99; 1.06; 1.09; 1.11; 1.22; 1.21; 1.24; 1.16; 1.13; 1.09; 1.07; 1.07 and 1.07; the last two are only provisional and may be revised next month.