Specialized ratios are sometimes used in specific industries. For example, the so-called book-to-bill ratio is closely watched for semiconductor manufacturers. A ratio of 0.93 indicates that for every $100 worth of chips shipped over some period, only $93 worth of new orders is received. In February 2006, the semiconductor equipment industry’s book-to bill reached 1.01, compared to 0.98 during the month of January 2006. The book-to-bill ratio reached a low of 0.78 during October 2006. The three-month average of worldwide bookings in January 2006 was $1.30 billion, an increase of 6 percent over January 2005, while the three-month average of billings in February 2006 was $1.29 billion, a 2 percent increase from February 2005. What is this ratio intended to measure? Why do you think it is so closely watched?