And according to my royalty statement, this book sold 7181 copies by end of the accounting period, which was last summer. (adistantsoil.com)
Some publishers may agree to pay within 30 days of the end of the accounting period. (fonerbooks.com)
Most commonly the big ranges happen near the end of accounting periods, or at minor financial panics, whether for legitimate reasons (LTCM, 9/11), or dubious reasons (Y2K). (alephblog.com)