Want to be a billionaire? The largest jackpot in U.S. history will be drawn on Tuesday night. The Mega Millions grand prize is now at $1.6 billion — the latest in a streak of record-setting jackpots. The odds are low, about one in 300 million. But the sales are high, especially following a change Mega Millions made in October 2017. 

“We tweaked the prize structure to make it a little bit harder to win the top jackpot,” said Gordon Medenica, lead director at Mega Millions.

The less jackpots are won, the more time the grand prize has to grow and the more sales are made. Powerball made a similar tweak in 2015. 

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