Johnston] NAVAHO POPULATION 169 



For the period 1920 to 1957, the majority of the Navaho child- 

 woman ratios display a marked uniformity. The major exceptions 

 consist in the ratios obtained from the enrolled populations in 1939 

 and 1957. The deficiencies in these rolls have already been commented 

 upon in the first part of this chapter. The remaining ratios fall within 

 a range from 720 to 792, with a simple (unweighted) average of 760. 

 It is interesting to note, in this connection, that the coiTesponding 

 average infant-child ratio, calculated for those populations reporting 

 the number of children under 1, comes to only 17.64 percent during 

 this period.^ 



The 1960 census returns are enlightening in this regard. The re- 

 ported age-sex distribution for non-Whites residing within the 

 boundaries of the Navajo Keservation yields a child-woman ratio of 

 942 (see table 32) and an infant-child ratio of 23.3 j)ercent. Since 

 there is little evidence of a recent upsurge of Navaho fertility, this 

 very high child-woman ratio suggests either that women of child- 

 bearing ages were seriously miderenumerated in 1960, or young 

 children were seriously underenumerated among other Navaho popu- 

 lations in the 1920-57 period. There is some plausibility in both argu- 

 ments. The reported infant-child ratio in 1960 suggests that infants 

 were not undercounted in 1960. If we accept this sensible ratio as 

 given, it is possible to develop an "adjusted" child-woman ratio for 

 the earlier Navaho populations. This adjustment raises the average 

 child- woman ratio for these populations from 760 to 816.^ 



If we now apply the rough calculation outlined in footnote 6, page 

 155, to this adjusted ratio, we obtain a crude birth rate in the neighbor- 

 hood of 41 per 1,000. As noted previously, this rate is not reported 

 for any Navaho population until 1956 and 1957. 



Much of the preceding analysis of Navaho vital rates has been 

 focused upon certain indicators of the underregistration of Navaho 

 births and deaths during selected years or periods. Obviously, this 

 focus ignores the equally fundamental problem of determining ac- 

 curate base population figures. In the case of the Navaho-Hopi 

 population combined, the variation that can result in the crude birth 

 rate, as obtained by dividing a given number of registered births by 

 different base figaires, is shown in table 33. 



The lowest derived crude birth rate shown in this table is obtained 

 by using the total population enrolled on both the Navaho and Hopi 



' The child-woman ratio for this latter group of Navaho populations also happens to 

 average exactly 760. 



8 This adjustment procedure is as follows : If 23.3 percent of all children under 5 are 

 under 1 year of age, the number of children under 1 must amount to 30.4 percent of those 

 aged 1 to 4. Given an average of 760 children under 5 per 1,000 women 15 to 49 years, and 

 an infant-child ratio of 17.64, the number of children under 1 is 760 times 0.1764, or 134. 

 This implies that there are 626 children aged 1 to 4 years (760 minus 134). Now, if we 

 assume that the "true" infant-child ratio is 23.3 percent, the number of children under 1 

 should amount to 30.4 percent of the number aged 1 to 4, or 190. The adjusted child- 

 woman ratio therefore comes to 626 plus 190, or 816. 



