in early childhood. Gupta claims that cultural factors provide the overwhelming explanation for the "missing" females." [ 53 ] "The Guanyin Who Sends Children" in a temple in the small town of Danshan , Sichuan . The disparity in the sex ratio at birth increases dramatically after the first birth, for which the ratios remained steadily within the natural baseline over the 20 year interval between 1980 and 1999. Thus, a large majority of couples appear to accept the outcome of the first pregnancy, whether it is a boy or a girl. If the first child is a girl, and they are able to have a second child, then a couple may take extraordinary steps to assure that the second child is a boy. If a couple already has two or more boys, the sex ratio of higher parity births swings decidedly in a feminine direction. [ 54 ] This demographic evidence indicates that while families highly value having male offspring, a secondary norm of having a girl or having some balance in the sexes of children often comes into play. For example, a study based on the 1990 census found sex ratios of just 65 or 70 boys per 100 girls for births in families that already had two or more boys. [ 55 ] Another study found a similar pattern among both Han and non-Han nationalities in Xinjiang Province: a strong preference for girls in high parity births in families that had already borne two or more boys.