Progress bars in Achievements

are buggy sometimes:

http://i.imgur.com/j2AIPnm.jpg

Yes, it looks like the bar is off. I haven't noticed that but I wouldn't worry about it too much (just like when downloading something it says 50% complete and 5 mins remaining... but never is) - I rely on the count on the right being the correct number. Keep an eye on that each time you make a book.