Sex ratio

Topic: Measuring Development: Income, HDI and Sustainability · NCERT: Class 11, Ch 8 "Comparative Development Experiences of India and its Neighbours"

Meaning

Sex ratio is the number of females for every 1,000 males in a population. This is how India measures it. The international convention flips it: males per 100 females.

• Formula (Indian convention): Sex ratio = (Number of females ÷ Number of males) × 1,000

It matters because it shows gender discrimination that income data cannot show. A low sex ratio usually means girls are being removed through sex selection or neglect. NCERT names son preference (valuing boys more than girls) as the cause of low sex ratios in India, China and Pakistan.

Explanation

How it is measured

• Indian convention: females per 1,000 males. A figure below 1,000 means fewer women than men.
• International convention: males per 100 females. Here a figure above 100 means fewer women.
• Converting between them: India's 930 F per 1,000 M (2021–23) → (1,000 ÷ 930) × 100 ≈ 107.5 males per 100 females.
• Worked example (illustrative): a village has 500 men and 470 women.
• Sex ratio = 470 ÷ 500 × 1,000 = 940 females per 1,000 males.
• International form = 500 ÷ 470 × 100 ≈ 106 males per 100 females.

Three types, each telling a different story

• Overall sex ratio: females per 1,000 males across all ages. Longer female lives and male migration affect it.
• Child sex ratio (CSR): females per 1,000 males in the 0–6 age group. It shows recent discrimination.
• Sex ratio at birth (SRB): the number of female births per 1,000 male births [4]. It is the clearest sign of sex selection before birth.

What pushes it down

• Son preference: families want boys for income, old-age support and inheritance.
• Sex-selective abortion: ending a pregnancy because the baby is a girl.
• Neglect of girls: less food, care and healthcare after birth, so more girls die young.
• Son "meta-preference" (Economic Survey 2017-18):
• Parents keep having children until a son is born.
• So families that end up large have more girls, and small families have more boys.

• This skews the ratio even where no sex selection happens.

• Coercive population policy (China's case):

• The one-child norm came in 1979-80, and families still preferred sons.
• Many families used sex-selective abortion to make their one child a boy.
• China's sex ratio is now the lowest of the three countries: 898 (2021–23).

What pushes it up

• Women live longer than men, so the overall ratio rises as a population ages.
• Male out-migration: many men leave home for work, so they are missing from the local count.
• Laws against sex selection, girls' schooling and changing social norms raise the SRB over time.

In India

• Comparison (NCERT Class 11, Table 8.1, 2021–23, WDI 2024): India 930, China 898, Pakistan 948 females per 1,000 males.
• Census 2011: overall sex ratio 943. Child sex ratio (0–6) 918.
• NFHS-5 (2019-21): overall sex ratio 1,020. This was the first national survey to count more women than men.
• Rural 1,037, urban 985 [2][3].

• But the bias at birth remains: the NFHS-5 sex ratio at birth (births in the last 5 years) was only 929.

• SRS (Sample Registration System):

• It is run by the Office of the Registrar General, India (Ministry of Home Affairs).
• It is a year-round survey in randomly chosen villages and urban blocks. It gives yearly estimates for India and each state [4].
• SRB improved from 899 (2014) to 913 (2021) [4].

• SRB was 904 in 2017-19, up from 899 in 2016-18 [4].

• Economic Survey 2017-18: about 63 million "missing women" (women who should be alive but are not, because of sex selection and neglect) and about 21 million "unwanted girls" (girls born to parents who wanted a boy).

• Law and schemes:
• PCPNDT Act, 1994 (Pre-Conception and Pre-Natal Diagnostic Techniques Act): bans finding out the sex of a baby before birth.
• Beti Bachao Beti Padhao (January 2015): a scheme to stop sex selection and support girls' survival and education. Sex ratio at birth is one of the measures used to track its progress [2][3].

Don't confuse with

• Overall sex ratio vs Sex ratio at birth (SRB): the overall ratio covers all ages and is raised by women's longer lives and male migration. SRB counts only births, so it shows sex selection. In NFHS-5 (2019-21) the overall ratio was 1,020 but SRB was only 929.
• Child sex ratio (CSR): it covers only the 0–6 age group, not births alone and not all ages. Census 2011 put it at 918, against an overall 943.
• International sex ratio: it counts males per 100 females. A higher number means fewer women, which is the opposite of India's convention.
• Dependency ratio: this is about age (dependants per 100 working-age people aged 15–64), not sex. Both come from the same population data, so questions often mix them up.

Prelims Hooks

• India measures sex ratio as females per 1,000 males. The international convention is males per 100 females. India's 930 ≈ 107.5 males per 100 females.
• NFHS-5 (2019-21): overall 1,020 (rural 1,037, urban 985) [2][3], but SRB 929. A ratio above 1,000 does NOT mean the bias at birth has ended.
• Table 8.1 (2021–23): China has the lowest sex ratio (898), India 930, Pakistan 948. China's low figure is linked to the one-child norm (1979-80).
• SRS is run by the Office of the Registrar General, India (Ministry of Home Affairs), not by MoSPI or NFHS. SRS SRB went from 899 (2014) to 913 (2021) [4].
• Census 2011: overall 943, child sex ratio (0–6) 918.
• PCPNDT Act, 1994 bans sex determination before birth. Beti Bachao Beti Padhao began in January 2015 and tracks progress using SRB [2][3].

Mains Points

• The headline figure hides the bias: an overall ratio of 1,020 (NFHS-5, 2019-21) sits next to an SRB of 929. The higher overall figure comes mostly from women living longer and men migrating for work. Discrimination against girls before birth continues. The Economic Survey 2017-18 estimates ~63 million missing women and ~21 million unwanted girls. This is why development cannot be judged by income alone. (GS-I/II)
• Law alone is not enough: the PCPNDT Act (1994) and BBBP (2015) have helped, and SRB has risen from 899 (2014) to 913 (2021) [4]. But son meta-preference means the root is social and economic. Stronger enforcement must go with changes that make daughters equally valued, such as women's property rights, girls' education and old-age security that does not depend on sons. (GS-II: welfare schemes)
• Coercion vs development: China's one-child norm cut population growth quickly. Combined with son preference, it also gave China the lowest sex ratio of the three countries (898, 2021–23), and it later moved to two-child (2016) and three-child (2021) policies. India brought fertility down mainly through education, health and choice. This shows that forcing population targets can damage gender balance for decades. (GS-II/III)

Related concepts

• Population growth rate
• Population density
• Son preference
• Total fertility rate
• Replacement level fertility
• Urbanisation
• Dependency ratio
• Demographic window of opportunity
• Ageing population
• Population pyramid

Read more

• Demographic indicators of development