According to UNDP Human Development Index, China has the most skewed gender birth ratio (121.2: 100) is the world, not-very-closely followed by Armenia (116.5: 100) and Azerbaijan (115.6:100). By looking at the top 15 countries, it is unsurprising to find some Asian neighbors: Korea, India, Hong Kong and Singapore, which have birth ratios lower than 1.1. China was once enjoying such level of birth ratio (which is already quite skewed) back to the 1990s, which makes the Sharp rise in the past 20 years even more astonishing. It is hard to believe the gender selection or abortion not playing a significant role behind the ratio.
What about the pattern of birth ratio back to 1990s:
China was then ranked the 2nd in the world, following South Korea. What is obvious from the graphs is that the birth ratio has been more skewed in 2010 than in 1990. One explanation is the effect of gender selection prevailing in quite a few developing countries. Another would be some findings that giving birth at a latter stage of life (which becomes increasingly common in certain countries) tends to increase the chance of having a male baby than a female one.
To put it in a bigger picture, one could find the most skewed ratio happens in countries with medium level of human development; in addition, Asian people tend to have more boys for every 100 girls than the Arab people:
|East Asia and the Pacific||108.5||116.0|
|Europe and Central Asia||104.4||105.6|
|Latin America and the Caribbean||103.8||104.2|
|Very high human development||105.5||105.6|
|High human development||104.2||104.8|
|Medium human development||107.8||112.2|
|Low human development||102.1||102.5|
|Least developed countries||102.2||102.5|
Given the huge Chinese population, we need to worry in the future not only about how to deal with the large CA surplus but also about handling the huge male surplus.