Population sex ratio (males per 100 females)
In the human species the ratio between males and females at birth is slightly biased towards the male sex. The natural “sex ratio at birth” is often considered to be around 105. This means that at birth on average, there are 105 males for every 100 females.
Nature provides that the number of newborn males slightly outnumber newborn females because as they grow up, men are at a higher risk of dying than women not only due to sex differentials in natural death rates, but also due to higher risk from external causes (accidents, injuries, violence, war casualties). Thus, the sex ratio of total population is expected to equalize. Instead if a country’s population sex ratio does not equalize or rather exceeds* the 105-threshold, it means societies with a dominating preference for male child tend to intervene in nature and reduce the number of born girl child by sex-selective abortion and infanticide.
(*An under-registration of female births also contributes to sex ratios at birth above the natural level).
Because women account for one-half of a country’s potential, balanced sex ratio is desirable. Besides, gender imbalances have been known in human history to cause serious negative consequences for the society in the long run.
Situation in SEAR
Over last 20 years (from 1990 to 2010) the ratio of number of males to per 100 females has declined in all SEAR countries except Bhutan, Indonesia, and DPRK. While in Bhutan it increased by eight percentage points, in Indonesia and DPRK the increase was modest by one percent. Sharpest decline was in Sri Lanka, Nepal, Maldives, and Bangladesh in that order. By 2010, only two countries (India and Bhutan) in the Region continue to have skewed (above 105) sex ratio.
On the other hand, of the three countries ( DPR Korea, Myanmar, and Thailand) which had higher percentage of females than males, two ( Myanmar and Thailand) continued to do so at still higher rate in 2010 but it slowed down in DPR Korea in favor of males.
Although women normally outnumber men beyond age 60, somehow it is not so in three SEAR countries (Bhutan, Maldives, and Bangladesh) where sex ratio in 60+ population is at 130, 113, and 108 respectively. This may be due to anomalies in enumeration of age and sex specific population data.
(Note: Unlike UN, some countries like. India report sex ratio as number of females per 100 males in their country publications. There the concern is to raise up the low sex ratio in order to balance the population by sex. But as per norms, in UN publication it translates to bring down the high sex ratio).