There’s a buying frenzy for the tickets to the July 29 lottery drawing. That’s making the jackpot bigger. It’s also making your ticket worth less.

How can that be? With more tickets sold, there’s a greater chance that, when you win, you’ll be sharing the prize.

You probably know the odds of winning—302.6 million to 1. You might not know the odds that, if you are a winner, you will be the only one. Your chance of that outcome is only 1 in 10.

The lottery operators haven’t released ticket volumes yet, but they keep talking about how big the jackpot has gotten. The latest press release number on that, $1.28 billion, suggests ticket sales in the neighborhood of 700 million.

It would seem that some people out there are buying multiple tickets. Do they think the $2 tickets are worth $4 each? Maybe they do. Divide the jackpot by the odds of getting the right six numbers and you come up with a $4 answer.

Sorry. The value of each ticket is now 71 cents, down from 82 cents yesterday.

Here’s my updated valuation scorecard:

Go ahead and fantasize about winning the big prize. But make your dream more realistic by assuming that you’ll have company in the winners circle.

I’ll hazard a guess: There will be either two or three winners tonight.

Of course, there could be more than three. Or there might be none, in which case next week’s jackpot will be bigger still.

If you want to know how I came up with that low-down, rotten, spoilsport figure of 71 cents, the details are here:

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