scale economies

[Doug Henwood <dhenwood@xxxxxxxxx>]

Someone posted this to another list:

>Scale economies--the savings (in unit costs) that come with higher
>volumes of output--are typically exhausted rather rapidly in most
>industries.  The common estimate in the auto industry, for example, is that
>there are no cost savings beyond 7.5% of the U.S. car market.  At that
>volume, unit costs are as low as they can be driven with the existing
>technology.  There are virtually no industries in which a market share
>greater than 10% of the U.S. market is required to exhaust all scale
>economies--to reach the lowest (technologically) attainable cost per unit.

Does anyone know how true this is?

Doug