First-year sales of Rowling's new book will be less than 40% of the first-year sales of Deathly Hallows (44 million according to Wikipedia.)

Created by Anubhav on 2012-02-29; known on 2013-12-20; judged right by Grognor on 2013-12-24.

• Anubhav estimated 70% on 2012-02-29
• JoshuaZ estimated 60% on 2012-02-29
• Grognor estimated 57% on 2012-03-01
• gwern estimated 65% and said “adult novel, IIRC, so I expect it to get panned by critics” on 2012-03-01
• saturn estimated 85% and said “Very few adult novels sell 17 million copies. Her fame is a factor, but so is regression to the mean.” on 2012-03-02
• Grognor said “massively underconfident of me, I guess, but I was trying really REALLY hard to avoid anchoring, so I was spouting numbers in my head and silently yelling, “HOW MUCH ARE YOU ACTUALLY WILLING TO BET ON THIS”” on 2012-03-03
• saturn estimated 98% and said “I think I’m guilty of anchoring too. According to the list of best-selling books on wikipedia, when sequels are excluded, no author has ever published two books which both sold over 17 million copies.” on 2012-03-03
• gwern estimated 90% and said “wow. on the other hand, one would expect it to happen at some point as the global market for books expands; and if it’s going to happen, it will be with a beloved billionaire author with global name recognition – that is, Rowling.” on 2012-03-03
• Anubhav estimated 85% and said “Adjusting upward as per saturn. (Not going to adjust too far upward; bestsellers every decade are more bestselling than the decade before.)” on 2012-03-05
• Serge estimated 60% on 2012-03-06
• RandomThinker estimated 80% on 2012-03-07
• ahartell estimated 90% on 2012-03-07
• goillini90 estimated 90% on 2012-03-08
• modulus estimated 75% on 2012-03-09
• Grognor   judged this prediction right on 2013-12-24.