Where did all this money come from?

About 6 years ago there was somewhere around 600 billionaires on this planet. Today there are almost 3,000. There's easily 4 1/2 times as many billionaires on this planet today as there was 6 years ago. And the top 50 billionaires have an astronomical amount of money. It would be interesting to do a rough calculation. It wouldn't be surprising if the top 50 billionaires have as much money as the 600 billionaires had just a few years ago. Need to do the math on that though. Where is all this money coming from? I mean there's still roughly 7 billion people. are the rest of us that much poorer? Why do they need to expand the money supply? If there's the same number of people it seems like the same amount of money should work. But as any politician can tell you it doesn't.