http://cs.bloodhorse.com/blogs/market-watch/archive/2014/11/19/book-size-signals-fluctuating-popularity-for-stallions.aspxA sire's career typically hinges on his first 2-year-olds, no matter what the initial market opinion was of the horse when he first entered stud. Occasionally that first crop vaults a stallion from obscurity, but more often the opposite happens when theenCommunityServer 2007.1 (Build: 20917.1142)