170 



BUREAU OF AMERICAN ETHNOLOGY 



[Bull. 197 



rolls in 1950 as a base figure. One might justify the use of this high 

 figure on the grounds that all births occurring among members of 

 this enrolled population, and no other births, should theoretically 

 be registered as Navaho or Hopi. The resultant rate, as shown in 

 table 33, is 3.4 percent lower than the official rate for this year. 



Table 33. — Estimates of the crude birth rate, Navaho-Hopi agency areas — 1950 



i Bureau of Indian Affairs, 1954 a, p. 14. In this report, a total of 6,901 live births were reported for 

 the Navaho-Hopi agencies for the 3 years, 1949, 1950, and 1951. This total produces an average of 2,300 

 annual live births at this time. 



' The number of births during the year, divided by the average population in that year, times 1,000 gives 

 the Crude birth rate. The official rate is 32.7. 



2 These differences were calculated by using the official crude birth rate of 32.7 as a base. 



* Bureau of Indian Affairs, 1954 c, p. 18. 



• The total is derived from the reported number of births and the birth rate, assuming that the latter 

 falls between 32.65 and 32.75. 



« Bureau of the Census, 1953 a, p. 62. 



The next rate sliown in the table is the official rate for that year. 

 The estimated population that is derived from this official rate and 

 the number of births reported for that year imply that over 2,000 

 enrolled Navahos and Hopis are unaccounted for in the official rate. 



The remaining three rates were calculated merely to illustrate the 

 effects of progressively restricted assumptions in regard to the base 

 population whose fertility is represented by the births reported for 

 that year. If we assume, for example, that only births occurring 

 among Navahos and Hopis residing in the service area surrounding 

 the two reservations are likely to be properly registered as such, we 

 derive a crude birth rate of 34.3, which is 4.9 percent higher than 

 the official rate. Alternatively, using the total enumerated Navaho 

 and Hopi population, comprising all Indians whose usual residence 

 was within the Navaho and Hopi agency areas as of April 1, 1950, 

 we obtain a crude birth rate of 35 per 1,000.^ Finally, if we were 

 to assume that births occurring among Navahos or Hopis residing 

 outside the confines of their respective reservations were not likely to 

 be registered as such, we might use the resident population of the 

 two reservations as a base figure. This produces a crude birth rate 



* For the limited purpose of this exposition, it was not deemed necessary to adjust the 

 official census figures in order to provide an estimate of the midyear population. Such an 

 adjustment would have the effect of reducing the derived crude birth rate from 35.0 to 

 about 34.8 per 1,000. 



