North America-based semiconductor manufacturers saw billings and bookings drop considerably in the first two months of 2009 to the worst levels in 18 years, according to information collected by a trade organization. The Semiconductor Equipment and Materials International, or SEMI, said in its report that semiconductor-equipment makers posted a three-month average of $263.5 million in bookings in February, down 5% from $277.2 million in January and 78% from $579.1 million in the final month of 2008. The three-month average of billings in February was $546.1 million, down 7% sequentially and about 58% from a year ago. The book-to-bill ratio, which measures the worldwide bookings and billings for North American-based semiconductor equipment manufacturers, dropped to 0.48 in February, up slightly from January's rate of 0.47 but down sharply from 0.86 in December. "These are the lowest bookings levels we've seen since SEMI began compiling data for the book-to-bill program in 1991," said Dan Tracy, senior director of Industry Research and Statistics at SEMI. "Spending and investments remain at minimal levels as the semiconductor industry waits for clearer signals indicating improvement in end market demand." SEMI is an industry association that serves manufacturing supply chains of semiconductor devices. Its report tracks billings and bookings worldwide of North American-headquartered manufacturers of equipment used to manufacture semiconductor devices, not billings and bookings of the chips themselves. The data contained in this release were compiled by David Powell, Inc., an independent financial services firm, without audit, from data submitted directly by the participants, SEMI said in its report.