The Curta.org Bulletin Board

[Rubberswan]

First time poster here!

I've been thinking about the survival rates are for mechanical calculators in general, and Curtas in particular. I suspect that the survival rate for large electro-mechanical desktop calculators (e.g. Friden and Marchant) is very low (less than one per-cent), and that the survival rate for hand-cranked desktop machines is a little higher (but probably still only one or two per-cent).

However, I strongly suspect that the survival rates for Curtas is much higher. We obviously have the machines on the List of Curtas, but this is clearly a subset of Curtas 'in the wild' - my two aren't on it!

So, what it boils down to is the question: How many Curtas aren't on the list? Twice as many? Ten times as many?

The list contains about 1250 Curtas out of a total production of about 140000 - roughly 1 per-cent. So how many really survive? 5 per-cent? 50 per-cent?

Any thoughts?

Kindest Regards
John Scriven (UK)
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Curta 1 - 61153
Curta 2 - 508965

[murff]

Hi John
Interesting question ... and difficult to find the real numbers.

From my sources I would estimate as following:
- 4% to 5% recorded in different lists and publications on the web (not all public), most of them are traded in the last 10 years
- 0.5% to 1% are are traded each year
- maybe another 3% to 4% are waiting to discover...

So maybe 10000 to 15000 units survived
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:: m u r f f
:: curta.li

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