If administrative assistants at Bookworm Publications make phone follow-ups after textbook reviews, more colleges and universities will adopt a x + 840 new statistics book. The publisher noticed that new book sales varied in the second year according to S(x) = A0 - , where S is total sales x² and x is the number of phone calls made to colleges which have adopted the book. A denotes the sales from the previous year. Assuming A0 = 2000, what sales can Bookworm Publications expect if they make 60 follow-up phone calls? Round your answer to two decimal places if necessary.