INTEKTOLL TRUNK NET LOSS MAINTENANCE 967 



Fig. 5 — Combined template on stroke chart. 



By use of this information the approximate bias is determined. The 

 scale of the bias values on the stroke sheet is shown in ^^ db steps along 

 the left-hand edge of the "Line Tots. (A)" column, and bias is deter- 

 mined to the nearest }^-i db. If the two cumulative totals differ from each 

 other by less than 25 per cent of the larger value, an arrow indicating 

 the bias is placed midway between the two class lines representing these 

 cumulative totals. Its value is read on the bias scale. If the two cumula- 

 tive totals differ from each other by 25 per cent or more of the larger 

 value, an arrow indicating the bias is placed ^?^ of the distance between 

 the two class lines representing these cumulative totals and nearer the 

 larger value. In Fig. 4, since 246 minus 166 (80) is greater than 25 per 

 cent of 246 (61.5), the arrow is placed ^4 of the way from the line repre- 

 senting 166 toward the line representing 246; i.e., at the — 3>^ db point 

 on the bias scale. A second arrow is placed at the corresponding point on 

 the tally 1 line. 



As shown in Fig. 5, a combined template is then placed over the chart 

 so that the center line of the template coincides with the two arrows. 

 Along the center line of the template there is a scale indicating numbers 

 of measurements from 50 throvigh 700. The template is moved horizon- 

 tally so that the point on the scale corresponding to the grand total of 

 measurements (533 in the example) is placed on the 1 tally line. En\^elope 



