A book titled "Manthropology: The Science of Why the Modern Male Is Not the Man He Used to Be" by Peter McAllister (bahahaha I just realized that's the same name from Home Alone).

Everything in the book should be taken as liberal interpretation of history, however that being said he does cite where he gets facts and figures from so you can do your own research of the subjects.

Here's a source of the 30k figure https://books.google.com/books?id=QMgsAwAAQBAJ&pg=PA74&lpg=P...

Here's an article that actually puts Diocles worth 15 billion https://www.telegraph.co.uk/news/newstopics/howaboutthat/794...