If deduction be made of the employing and salaried classes, about 7.7 per cent of all persons occupied were organized. If, further, deduction be made of agricultural, clerical, publicly employed, commercial and domestic workers, about 16 per cent of the remaining 13,760,000 persons are organized (of women 3.7 per cent). Among the occupations most highly organized are those of railway conductors (87 per cent) and engineers (74 per cent). In the building trades about 16 per cent are organized, of granite cutters 69 per cent, masons 39 per cent, plasterers 32 per cent, carpenters 21 per cent, and painters 17 per cent. Similar striking differences appear among the occupations in the printing industry; of stereotypers 90 per cent are organized and of compositors only 35 per cent. These figures point to inherent differences in the conditions favoring organization. Even in the same craft a high degree of organization may be found in the cities and little or none in the smaller towns (e.g., in the case of the printing and building trades in general).[3] § 6. #Collective bargaining.# The fundamental policy of trade unions is the substitution, for the individual wage bargain, of collective bargaining between the delegated representatives of the working men and the employer, or group of employers, or their representatives. The wage-earners bargaining collectively may be those of a single establishment, or of a group of establishments in the same locality, or of a wider territory even national in extent. Accordingly, they are represented in the negotiations by trade-union officials with narrower or wider jurisdiction. Employers in some cases had tacit understandings with each other before laborers were organized. But in many cases the individual employer was at a marked disadvantage after the organization of his employees. The result has been the rapid spread of employers' organizations, so that in industries where laborers are highly organized, two-sided collective bargaining has become more and more usual. A large part of the effort of trade unions is directed toward ensuring the use of collective bargaining. This is the purpose of many of their demands, even of some that hardly appear to have any such consideration. Collective bargaining practically necessitates the use of "the standard rate," since only with reference to some standard rate, a market price for labor, is it possible for a wage contract to be made by labor officials for a group of men. The standard rate may be a piece price or a time price, and in many cases the unions strive to secure the latter as more convenient for their purposes. The standard time rate usually is but a minimum and many of the more skilful workers receive wages above the minimum. But the standard minimum tends to become also the maximum in many cases, the more so when the union has succeeded in enforcing a pretty high standard rate.