Too many otherwise excellent reports contain figures which give the impression of great accuracy when in reality the figures may be only the crudest approximations. Except in financial statements, it is a safe rule to use ciphers whenever possible at the right of all numbers of great size. The use of the ciphers greatly simplifies the grasping of the figures by the reader, and, at the same time, it helps to avoid the impression of an accuracy which is not warranted by the methods of collecting the data.

A recent government report* contained this statement: "The cotton crop of last year (1911) aggregated 16,250,276 500-pound

* "The Packing and Marketing of Cotton," by John M. Carson.

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bales, the total value of which is $1,000,000,000 and, including the seed, $1,200,000,000." The figure for the number of bales implies that every single bale of cotton raised in the United States was accounted for and that these figures are absolutely accurate down to one bale of cotton. This denotes an accuracy of 1 part in 16,000,000 parts, or an accuracy within 0.000006 per cent. It is very doubtful indeed whether the figures for the cotton crop are accurate within 1,000 or even 10,000 bales. Suppose a possible error of 10,000 bales were assumed, and the cotton crop put down as 16,250,000 bales, the accuracy would still be 1 in 1,625, or within 0.06 per cent. For most purposes it would be much preferable to use the round number 16,250,000 instead of the detailed figures which were given in the Government report. The particular report from which the figures are taken is not a tabulation, but a written report in regard to the methods used for packing cotton. Since the report was intended to be read by merchants and planters, rather than by statisticians, it is all the more important that the figures should be presented in round numbers so that they may be easily grasped.