What a Pound of Change is Worth

Posted to Statistics  |  Tags: ,  |  Nathan Yau

After seeing his friend’s CoinStar receipt for 27 pounds of coins that equalled $256.14, Dan Kozikowski dug deeper and estimated what a pound of change is worth, on average.

Now, to finish out the analysis, let’s tie this back to weight. Fortunately, the U.S. Mint standardizes and publishes the weight of each coin here. With that in hand… drumroll please… we’d expect about 34.9 quarters, 19.8 dimes, 11.5 nickels, and 61.2 pennies in a New York pound of coins, for a total value of $12.00. A Boston pound is worth slightly less&mdsah;$11.81.

I love it when people analyze the everyday. (Although I’m sure CoinStar looks at distributions like this all the time for storage supply something or other.)

Alas, the coin distribution of Kozikowski’s friend didn’t quite match the estimate, as shown in the graph above. He attributes it to the friend spending quarters, dimes, and nickels before going to the CoinStar. There are only fewer quarters though and almost twice the expected count of dimes and nickels, so the model needs to be refined.

3 Comments

  • He found fewer quarters because quarters are actually useful, for laundry or vending machines. I keep and use quarters that I get as change but put everything else in a jar. The friend probably spent the quarters in the normal course of life.

  • just read this article and googled “boston pound vs new york pound.” Found 4 links to this same article, and no useful info. what’s the difference?

  • Because the two cities have different sales taxes, the distribution of prices — and therefore, expected distribution of coins — varies between Boston and New York. This is why the projected value of a pound of coins changes.

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