• The Powerball jackpot surged to an estimated $1.73 billion without a winning ticket on Monday.
• The next winner has two payout options: an annuity worth $1.73 billion or a lump sum valued at $756.6 million.
• Experts say there are a few reasons why lottery grand prizes have grown in recent years.
• The next Powerball drawing is Wednesday at 10:59 p.m. ET.

The Powerball jackpot surged to an estimated $1.73 billion, the second-largest prize in the game's history, without a winning ticket on Monday.

While it's the first time Powerball has seen back-to-back billion-dollar grand prize cycles, lottery jackpots have gotten bigger more frequently over the past several years, experts say.

The next Powerball drawing is Wednesday at 10:59 p.m. ET, and the winner has two payout options: an annuity worth $1.73 billion or a lump sum valued at $756.6 million. Both are pretax estimates.

One reason for more frequent large Powerball jackpots is a 2015 change to the game's matrix, according to J. Bret Toyne, executive director of the Multi-State Lottery Association, which runs Powerball. 

Powerball players must correctly choose all six numbers to win the grand prize — five white balls and one red ball for the jackpot.

In 2015, Powerball added more numbers for the white and red balls, which decreased the chance of hitting the jackpot. Currently, there is roughly a 1 in 292 million chance of winning the grand prize, compared to the previous odds of about 1 in 175 million, Toyne said.

Plus, the game added a Monday drawing in 2021, he said. Without a jackpot winner, the estimated grand prize keeps rolling over until a player chooses all six numbers.

Higher interest rates have boosted jackpots

Another reason for bigger lottery jackpots over the past couple of years has been rising interest rates, said Akshay Khanna, CEO of Jackpot.com, which sells state lottery tickets.

Similar to savings accounts, higher interest rates allow jackpots to grow more quickly over time, he said. "The higher the interest rates, the more you're earning on that pool of capital."

Of course, this may shift once the Federal Reserve reverses its policy and begins cutting interest rates.

In the meantime, more online sales options and the "media frenzy" as jackpots grow have also contributed to higher grand prizes, Khanna said. "The combination of these two things is really driving these higher and higher jackpots, particularly in the last two years," he said.

Wednesday's Powerball drawing comes less than three months since a single ticket sold in California won the game's $1.08 billion jackpot. Meanwhile, the Mega Millions jackpot is back down to $48 million and the odds of winning that prize are roughly 1 in 302 million. 

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