They’re not something to watch in terms of working out exactly how many copies of a particular book have been sold, or whether a title is profitable or not. But they do give a broad indication of how well the books are doing as compared to one another. For example, it is entirely possible for the sales on, say, CAPTAIN AMERICA, to go up, but for the ranking of CAPTAIN AMERICA on those charts to go down–it all depends on how many other titles were released that month and how well all of them did. So those standings are just relative to one another in a given month, they can’t even be accurately tracked from month to month, in a “CAP was at #2 last month and now it’s at #4, the sky is falling!” sort of a way–because that book at #4 may have sold more copies. And as I tell my editors, the only number that counts is the number of copies that you sell.