owners' daughters for whom reports were obtained, 96.5 per cent were promoted as compared with 77.2 per cent of tenants' daughters; while 88.6 per cent of owners' sons were promoted as compared with 65.6 per cent of tenants' sons. The same fact is brought out in an even more striking way by the percentages of the four groups that had been retained.

TABLE 34.-Promotions of children of owners and of tenants.

If these conditions are general, they would indicate that the average tenants' child is more backward in school attainments than the average owners' child. That this is the case is indicated by Table 35, showing the average age and grade of the four groups of children. For the two groups of grades-the first four grades, and the fifth to eighth grades, inclusive-the tenants' children are from six months to a year older than the owners' children. In other words, the tenants' child is from six months to a year behind the owners' child in grade attainment. The data on pupils above the eighth grade do not show this same backwardness of tenants' as compared with owners' children. However, the numbers involved in this case are too small to make the data reliable.

TABLE 35.-Average age of pupils in three groups of grades, classified by tenure status of father and by sex, for pupils in five black-land country schools.

These unfavorable educational conditions associated with tenancy are, no doubt, not all attributable to tenancy. Tenants, as has been shown, are much poorer than owners; and this difference in the eco

nomic status of the two classes causes tenants to draw more heavily on their children's time for farm labor than do owners. If the tenant were an owner, with his present wealth, he would doubtless still demand more field work of his child than the average owner now demands of his child. Consequently, it is impossible to say how much of the backwardness of the tenant's child is attributable to tenure and how much to financial status.

Regardless of this question, it is quite evident that the tenant's child is having to bear a heavier burden than is the owner's child. And it is evident that some of the more important rural school problems of the area are closely bound up with the problem of tenancy, and that they must be solved in conjunction with solutions of the tenure problem.

ADDITIONAL COPIES

OF THIS PUBLICATION MAY BE PROCURED FROM
THE SUPERINTENDENT OF DOCUMENTS
GOVERNMENT PRINTING OFFICE
WASHINGTON, D. c.

AT

10 CENTS PER COPY

Large yields of milk and butterfat per cow are the aim of most dairymen and also of most breeders of dairy cattle. It is plain that the income from a farm dairy depends ultimately on the earning capacity of the individual units in the herd-the cows. The purpose of the work here reported is to analyze a large number of records and to show the relation between the productivity of cows and the income received by their owners. The records used are those of cowtesting associations.

Such an association, as ordinarily conducted in this country, is an organization of about 26 dairy farmers who cooperatively employ a man to test their cows for production of milk and butterfat. As the tester can ordinarily test only one herd a day, the 26 dairy herds furnish employment for each working day in the month. Records from a large number of cow-testing associations are a veritable mine of useful information. They cover a wide range of interesting dairy topics and show actual production under normal farm conditions. For the purpose of this bulletin the records of individual cows from 96 cow-testing associations have been tabulated to show the relation of production to cost of feed and to income over cost of feed and

91234°-22-1

to ascertain the best methods of dairy-herd management. Some of the 96 associations furnished records for more than one year. In such cases the records for each year were tabulated as though they were from different associations. On that basis the 96 associations furnished 120 sets of records. Therefore, to determine from these figures the average number of cows on test in an association we must consider each set of records as a separate association.

In the 120 sets of records there were 2,939 herds and 41,990 cows on test. The study covered the period 1910 to 1920, inclusive; but every cow record was for a period of one year, the records of less than one year being included only when making herd and association summaries. In all other tabulations 12 months' records only were used.

FIG. 1.-Location of the 96 cow-testing associations whose records were tabulated.

It is well known that cows having high-production records are generally more profitable than those whose production records are not so high, and this bulletin shows the rate at which income over feed cost advances as average production increases.

CHARACTER OF DATA USED.

Figure 1 shows the distribution of the cow-testing associations whose records were tabulated:

So far as practicable the records of each association were studied independently of the others before being grouped into general tables. In this way any differences due to geographical location were noted and interpreted.

The first cow-testing association in the United States began work in Newaygo County, Mich., in 1906. On July 1, 1921, there were

452 active associations in the United States. The map (fig. 2) shows the location of these associations.

HOW THE RECORDS WERE STUDIED.

The individual cow record includes the name, breed, age, and weight of the cow. It also includes date of freshening, names of dam and sire, months in milk, pounds of milk produced, butterfat test, pounds of butterfat, price of product, total value of product, feed consumed, days on pasture, cost of pasture, cost of roughage, cost of grain, income over cost of feed, returns for $1 expended for feed, feed cost per pound of butterfat, and feed cost per 100 pounds of milk.

In making the herd and association summaries here discussed the records of all cows on test 4 months or more were included. That is

FIG. 2.-Location of the 452 cow-testing associations in the United States, July 1, 1921.

the way such summaries are made by the testers in nearly all the cow-testing associations in the United States. In all other tabulations only the records of cows that were on test 12 consecutive months and had breed and age given were used. The reason for discarding the shorter records in making tabulations was to avoid possible error due to the use of such records. The possible error due to a use of such records. however, is probably negligible, as average yield, cost, and income proved to be about the same per cow-year 1 when the records of all cows on test were included as when only the records of those on test 12 months were included. (See Table 1.) This indicates that the herd and association summaries as now ob

1 See footnote to Table 1.