4.44 seconds |
|Shortest Individual Period 1.60 seconds |
|Average five shortest Individual Periods 1.65 seconds |
|Average ten shortest Individual Periods 1.80 seconds |
|Average Entire 100 Calls 3.160 seconds |
|Hourly Rate at which calls were being handled 1139 |
+-----------------------------------------------------------------+

Owing to the difficulty of securing accurate traffic data by means of a
stop watch, an automatic, electrical timing device, capable of
registering seconds and hundredths of a second, has been used in
studying the performance of this system in regular operation at
Ashtabula Harbor. The operators were not informed that the records were
being taken, and the data tabulated represents the work of two operators
in handling regular subscribers' calls. The figures in Table XI are
given by C. H. North as representing the total time consumed by the
operator from the time her line lamp was lighted until her work in
connection with the call was finished, and it included, therefore, the
pressing of the listening button, the receiving of the number from the
subscriber, repeating it back to him, setting up the connection on the
keys, and pressing the starting key.

It will be seen that the average time for each 100 calls is quite
uniform and is slightly over three seconds. The considerable variation
in the individual calls, ranging from a maximum of 12.40 seconds down to
a minimum of 1.60 seconds, is due almost entirely to the difference
between the subscribers in the speed with which they can give their
numbers. These figures indicate that, in each of the tests, calls were
being handled at the rate of more than one thousand per hour by each
operator.

The test of the subscriber's waiting time, _i. e._, the time that he
waited for the operator to answer, for one hundred calls made without
the knowledge of the operator, showed the results as given in Table XII,
in which a split second stop watch was used in making the observations.

TABLE XII

Subscribers' Waiting Time

+----------------------------------------------------------+
|Number of Calls Tested 100 |
|Longest Individual Period 5.20 seconds |
|Average 5 Longest Individual Periods 4.64 seconds |
|Average 10 Longest Individual Periods 3.80 seconds |
|Shortest Indi