North American-based manufacturers of semiconductor equipment posted a book-to-bill ratio of 0.88 for December 2011, up for the third consecutive month, according to SEMI. A book-to-bill of 0.88 means that US$88 worth of orders were received for every US$100 of product billed for the month.

The three-month average of worldwide bookings stood at US$1.16 billion in December 2011, new figures from SEMI show. The bookings figure is 18.5% more than the revised November level of US$997.2 million, but 26.7% below the US$1.58 billion in orders posted a year ago.

The billings figure came to US$1.32 billion in December, up 11.8% from the revised level of US$1.18 billion in November but 25.2% less than the December 2010 billings level of US$1.76 billion, according to SEMI.

"The December data reflects a further increase in bookings for semiconductor equipment," said Dan Tracy, senior director of Industry Research and Statistics at SEMI. "Recent capital spending announcements by leading device manufacturers indicate the potential for continued improvement in 2012."