320 APPLYING EFFICIENCY PBINCIPLES
ward will then cost 4.4 cents per hour, making the total
average standard cost of labor per hour, 26.4 cents.
The existing efficiency of price of labor would tben
be average standard cost divided by average actual
cost, 26.4-^-20=132 per cent.
330. Efficiency of distribution of labor can be determined
by time-motion studies; an example of such, a
study and of determinations from it is given in Table
6 and in Article 166. Usually it would take more time
than is desirable to spend on preliminaries, to make an
approximate determination of this factor of the efficiency
of labor, and it is therefore usually best at this
stage to assume that it is 100 per cent. This makes
the estimate of feasible saving on labor conservative,
as it is better that all preliminary estimates should
be.
331. A time study is an analysis of the use of a sample
of time, in which the total time is separated into
certain parts, the percentage of each of these elements
used or wasted is determined, and causes, if possible,
are determined for such losses as are detected. It is
evidently possible to analyze the use of sample lots
of materials in the same way, and to obtain corresponding
results, from which may be determined the efficiency
of use of materials. There is this difference,
that while a skilled time-study man can usually (though
of course not always) estimate approximately the
efficiency of the use of labor without the aid of any
one skilled in the particular process which is under
investigation, such aid is apt to be needed to estimate
the percentage of material scrap that should have been
saved.
This kind of an analytical study of the use of materials
has not attracted much attention in the literature