Statistics

[john1943]

I had seen a YouTube video about a very expensive penny and mentioned it to my wife. The result was her dumping over 20lbs of pennies (over 20,000) in my lap as well as nickels, dimes, quarters, half dollars, and dollars.

It turned out that she had been putting away her spare change for well over forty years. Much of it was in rolls of pennies and so a reasonable proportion of them are in good condition.

I got interested in errors because I am interested in how things are made. However, I know that it will be some time before I can accurately recognize errors but going through thousands of coins a few times helps.

In order to make the hunt for errors easier I decided to sort the pennies into decades and then years. Did a collection of cents acquired randomly reflect the number of pennies being minted each year?

I figured that as my wife was not a collector and indifferent to the change she regularly put away, the distribution of her coins should match the various quantities of pennies minted each year.

These are the results.

Not able to load the Excel file but the mint numbers are pretty much within two percentage points of the amount of cents stashed away by my wife when taking the years mint number as a percentage of the decades total and comparing it with the number of cents stashed away by my wife each year as a percentage of her total for the decade. Same for the nineties but in the 2000's the correspondence diverged as the advent of digital payments increased.

I think the results are remarkable in that they are almost congruent for the 1980s.
John

[mustbebob]

Did a collection of cents acquired randomly reflect the number of pennies being minted each year?

Not really, but it probably was more likely in the older days of coin making. There are so many variables concerning where coins were/are released. Now days, coins are placed into circulation through depository institutions (e.g. banks, savings and loans, credit unions, thrifts).

If you ever want to know how many coins are minted each year, that number is easily obtainable on the Internet.

[Kloccwork419]

I would listen to Bob when it come to that info. He still has every coin he searched the last 50 years and I bet nobody has a clue they arent in circulation. Lolol

[john1943]

That is why it seemed so strange to me that the figures for change stashed away by a single person, not a collector, reflected the mint figures so closely. Of course I did include special mint figures but as these were so small compared to the business mint that I felt it was worth including them as certainly some proof coins enter circulation. I showed the cumulative percentage of the mint # for the decade and the cumulative percentage of the change stashed away to see if there was any obvious deviations but the congruency, in my opinion, was quite interesting. The person with the change collection lived on the east coast until the early seventies and then in California. This is reflected in the mint mark quantities.
I am still learning the site and will try to upload an image with this message. Is this a lamination defect?
john

[MintErrors]

It could very well be. Take a closer look for yourself to see if that layer is slightly lifted up. My only concern is wht the split did not go through the L in "LIBERTY". Strange. Maybe it is just the angle of the photo. It looks too "clean" to be a die crack. The die cracks tend to be a little more jagged. It does not have the appearance of a post mint damage type scratch. It could have been a struck through fiber or other debris as well. It's hard to tell what it is.