Excellent examples of comparative records are shown in Figs. 18 and 19. Fig. 18 provides a detailed comparative record of labor costs, the costs of seven jobs being recorded on each sheet. This shows, for each operation, the number of pieces, hours, amount, average labor cost, and average time consumed. If on three orders, 2,000, 3,000 and 5,000 parts are made, this record will show the total cost of each order, the cost of each part, and by comparison, the relative cost when manufactured in different quantities. [Illustration: Fig. 20. Monthly Comparison of Costs of Standing or Expense Orders] To provide for an analysis of material costs, the form shown in Fig. 19 is used. This is similar to the form shown in Fig. 18, the difference being that it shows detailed costs of each separate kind of material. Fig. 19 is printed on the reverse of Fig. 18. The form is loose leaf and the sheets are filed in a binder in the order of part numbers. Fig. 20 is a card form used for a monthly comparison of costs of standing orders or expense orders, with labor and material costs separated. The form provides for a comparison of monthly costs covering a period of four years──a very valuable record. As an illustration of the manner of using this form, it will be supposed that machine shop repairs are made on order No. 460. Both material and labor are included in the cost of repairs. One of these cards would be used for this order and, at the end of each month, the totals of material and labor used on machine─shop repairs would be entered. The total would be extended in the third column. CONTINUOUS PROCESS FACTORIES =46.= A distinct class of manufacture, which involves certain special problems in cost accounting, is the business in which the process is continuous. For convenience, we refer to such factories as _continuous process factories_. Any factory in which a definite quantity of raw material is converted into a finished product, the quantity of the product not being definitely determined in advance, is classed as a continuous process factory. Examples are flour mills, sugar and salt refineries, nail mills, button and pin factories, and yarn mills. The problem in factories of this class is to find the total cost of production and the total number of units of production; the former divided by the latter will give the cost per unit. The cost of production includes the cost of material, labor, and expense. It is necessary, therefore, to keep an accurate record of material and supplies issued to the factory, just as is done in factories manufacturing goods on special orders. Labor costs should be recorded by departments, and the distribution of expense should be by departments, as far as possible. Forms similar to those shown in the preceding pages can be used.