I do know that occasionally, a publisher would deliberately put a "fake" mintage number in their listing. So if anyone ever copy-pasted their listing they'd know who to pursue for copyright infringement.
Most of the differences can probably be explained by different interpretations of the Mint Reports. The Mint Reports are fiscal year, which of course does not correlate to calendar year. Which of course may not necessarily correlate to the actual year on the die when in use.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis