Greatest advance for a book of fiction

It was reported in August 1992, that Berkeley Putnam paid $14 million (then £7.3 million) for the North American rights to Without Remorse by Tom Clancy (USA), representing the greatest advance for a single book. Without Remorse is a complex spy thriller featuring John Kelly (aka Mr Clark), character which appeared in Clancy's other bestseller and film adaptation Clear and Present Danger. Kelly is a former Navy SEAL and Vietnam veteran who is sent by the Pentagon on a mission to Vietnam whilst pursuing his own agenda for revenging the murder of a close friend.