THE LOW SEX RATIO IN NEGRO BIRTHS AND 

 ITS PROBABLE EXPLANATION. 



S. J. HOLMES, 

 UNIVERSITY OF CALIFORNIA. 



It has sometimes been stated that the ratio of male to female 

 births is lower among the Negroes than among whites. The 

 records of births published by the U. S. Census Reports for 1880, 

 1890, and 1900, gave very low sex ratios for the Negroes, 

 namely 100.25, 102.67, an d 99.80 respectively. The data on 

 births for these years were admittedly incomplete. Births were 

 estimated "by adding to the living childern under one year of 

 age as shown by the population returns, the number of those who 

 were born during the year ending May 31, but who died before 

 the end of the year, as shown by the returns of deaths." The 

 ridicuously low death rates estimated on the basis of the census 

 returns for 1880 and 1890 made it evident that reports of deaths 

 collected during the census year were very incomplete. The 

 deficiencies in the census of 1880 were estimated by Dr. J. S. 

 Billings as about thirty per cent., and those of 1890 were probably 

 even greater. It is quite natural that failures to report deaths 

 would affect most the data on the mortality of infants, especially 

 among the Negroes. That this is the case is evinced by the very 

 small proportion of infant deaths reported as compared with the 

 number of living children under one year of age, whereas it is well 

 known that the actual mortality rate among Negro infants is very 

 high. Inasmuch as male infants suffer an exceptionally high 

 death rate, the effect of basing estimates of births partly on data 

 which leave out a large proportion of infant deaths is to give a 

 sex ratio with too low a proportion of males. On account of the 

 higher infant mortality of the Negroes, to say nothing of more 

 numerous deficiencies in the records, the Negro sex ratio would 

 be reduced more than that of the whites. 



Aside from the rather unsatisfactory compilations published 

 in the Census Reports we had, until a few years ago, relatively 

 meager data on Negro births. Dr. J. D. Nichols has compiled 

 records for the District of Columbia (1874-02) and finds a sex 

 ratio in Negro births of 103.10. Beginning in 1915 the annual 



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