India's Population — Size and Growth
Historical Growth
| Census Year | Population | Growth Rate |
|---|---|---|
| 1901 | 23.8 crore | — |
| 1921 | 25.1 crore | 5.75% (lowest — "Year of Great Divide") |
| 1951 | 36.1 crore | 13.31% |
| 1981 | 68.3 crore | 24.66% (highest growth decade) |
| 2001 | 102.7 crore | 21.54% |
| 2011 | 121.0 crore | 17.64% |
| 2023 (est.) | ~144 crore | — |
India surpassed China as world's most populous nation in April 2023 (UN estimate).
1921 = Year of Great Divide: Population actually declined (1911–1921) due to Spanish flu pandemic (1918) and famines — the only decade of negative/near-zero growth in modern India.
Census 2011 — Key Data
India's Census 2011 is the 15th census; conducted by Registrar General of India.
Population Distribution
| Rank | State | Population |
|---|---|---|
| 1 | Uttar Pradesh | 19.98 crore |
| 2 | Maharashtra | 11.24 crore |
| 3 | Bihar | 10.41 crore |
| 4 | West Bengal | 9.13 crore |
| 5 | Andhra Pradesh (undivided) | 8.46 crore |
| 6 | Madhya Pradesh | 7.27 crore |
| 7 | Tamil Nadu | 7.21 crore |
| 8 | Rajasthan | 6.86 crore |
Least populous: Sikkim (6.1 lakh) Most populous UT: Delhi (1.68 crore)
Population Density
Density = persons per square kilometre
| Rank | State/UT | Density |
|---|---|---|
| Highest | West Bengal | 1,028/sq km |
| 2nd | Bihar | 1,106/sq km (Bihar is actually highest in states) |
| Lowest (state) | Arunachal Pradesh | 17/sq km |
Note: Bihar has highest density among states (1,106). West Bengal is second (1,028). Among UTs, Delhi is highest (11,320/sq km).
India average density: 382 persons/sq km (2011) Tamil Nadu density: 555/sq km
Literacy
National literacy rate (2011): 74.04%
| Category | Rate |
|---|---|
| Male literacy | 82.14% |
| Female literacy | 65.46% |
| Gender gap | ~17 percentage points |
Most literate states: 1. Kerala — 93.91% 2. Lakshadweep (UT) — 91.85% 3. Mizoram — 91.33%
Least literate states: 1. Bihar — 61.80% 2. Arunachal Pradesh — 65.38% 3. Rajasthan — 66.11%
Tamil Nadu literacy (2011): 80.09% (above national average; male 86.77%, female 73.44%)
Sex Ratio
National sex ratio (2011): 940 females per 1,000 males
| Rank | State | Sex Ratio |
|---|---|---|
| Highest | Kerala | 1,084 |
| 2nd | Tamil Nadu | 996 |
| 3rd | Andhra Pradesh | 993 |
| Lowest | Haryana | 879 |
| 2nd lowest | Sikkim | 890 |
Child Sex Ratio (0–6 years)
National child sex ratio (2011): 914 — down from 927 in 2001 — alarming trend
| Worst child sex ratio | State |
|---|---|
| 834 | Haryana |
| 846 | Punjab |
Tamil Nadu child sex ratio: 943 (above national average)
Laws against sex-selective practices:
- PCPNDT Act 1994 (amended 2003): Pre-Conception and Pre-Natal Diagnostic Techniques Act — prohibits determination of sex of foetus; bans sex-selective abortion
- Beti Bachao Beti Padhao scheme (2015): Focus on 100 worst sex ratio districts
Religious Composition (Census 2011)
| Religion | Population Share |
|---|---|
| Hindu | 79.8% |
| Muslim | 14.2% |
| Christian | 2.3% |
| Sikh | 1.7% |
| Buddhist | 0.7% |
| Jain | 0.4% |
| Others/not stated | 0.9% |
States with majority non-Hindu population:
- Jammu & Kashmir: Muslim majority
- Punjab: Sikh majority (~57.7%)
- Meghalaya, Mizoram, Nagaland: Christian majority
- Lakshadweep (UT): Muslim majority
Tamil Nadu (2011): Hindu 87.6%, Muslim 5.9%, Christian 6.1%
Scheduled Castes and Scheduled Tribes
| Category | Population | Share |
|---|---|---|
| Scheduled Castes (SC) | 20.14 crore | 16.6% |
| Scheduled Tribes (ST) | 10.43 crore | 8.6% |
States with highest SC population: Uttar Pradesh (4.06 crore), West Bengal (2.14 crore), Bihar (1.65 crore)
Tamil Nadu SC population: 14.96% of state population (Paraiyar, Pallar, Chakkiliyan are major SC communities)
States with highest ST population: Madhya Pradesh (1.53 crore), Maharashtra (1.05 crore), Odisha, Rajasthan, Jharkhand
Urbanisation
Key Data
- Urban population (2011): 377 million (31.16%)
- Up from 27.8% in 2001
- India has world's second-largest urban population (after China)
Types of urban areas in India: 1. Statutory towns: Have municipal bodies (Municipal Corporation, Municipality, Town Panchayat) 2. Census towns: Have 5,000+ population, 75%+ male workforce in non-agricultural work, density 400+/sq km — may not have municipal body
Mega-cities (10 million+, 2011):
- Mumbai: 12.4 million
- Delhi: 11 million (Delhi UA: largest)
- Kolkata, Bangalore, Chennai, Hyderabad: 4–8 million range
Million-plus cities (2011): 53 (up from 35 in 2001)
Tamil Nadu urbanisation: 48.4% — one of India's most urbanised states (national avg 31.16%) Chennai Metropolitan Area: ~8.7 million
Urbanisation Challenges
- Slums: 65.5 million slum dwellers (Census 2011); 1 in 3 urban residents lives in slum
- Water and sanitation: 70% urban India has piped water; sewerage coverage poor
- Traffic congestion: Average speed in Indian mega-cities falling
- Heat island effect: Urban areas 3–5°C warmer than surrounding rural areas
- Chennai: Pallikaranai marshland destruction; storm water drain encroachment; Day Zero 2019
Migration
Internal migration (within India):
- 450 million internal migrants (2011 census data + NSS)
- Largest flows: UP, Bihar → Delhi, Mumbai, Surat (construction, domestic work)
- Tamil Nadu: receives migrants from Andhra Pradesh (construction), Bihar (seasonal agricultural labour)
- Tamil Nadu also sends migrants: Gulf countries (remittances significant), Singapore, Malaysia
International migration:
- Non-Resident Indians (NRIs): 32 million Indians abroad
- Largest diaspora: USA (4.2 million), UAE (3.5 million), Malaysia (3 million), Saudi Arabia (2.5 million)
- Remittances: India is world's largest remittance recipient — $125 billion (2023)
- Tamil diaspora: Malaysia, Singapore, UK, Canada; also Sri Lanka (LTTE conflict legacy)
Demographic Dividend
What It Is
Demographic dividend = economic growth from a favourable age structure — a large working-age population (15–64) supporting a smaller dependent population (children + elderly).
Dependency ratio: (Population below 15 + above 64) / Working-age population × 100 India's total dependency ratio is falling — creating the demographic dividend window.
India's Window
- India's median age: ~28 years (2023) — young
- Working-age population: ~68% of total
- Peak of dividend: approximately 2030–2041
- India adds 12 million new workers to labour force annually
Conditions for dividend to materialise: 1. Quality education and skills: Only 25% of engineering graduates currently employable in formal sector 2. Manufacturing jobs: Services absorb fewer workers per rupee of growth than manufacturing 3. Female LFPR: Currently ~24% nationally; Tamil Nadu ~35% — India needs to close this gap 4. Health: Low child malnutrition, reduced disease burden
Risk of demographic burden: If young population is uneducated or unemployed, same age structure becomes a liability — social unrest, crime, wasted human capital.
Tamil Nadu: Already past peak of dividend phase — ageing population in some districts; fertility rate below replacement level (TFR ~1.7); focus must shift to productivity rather than numbers.
Fertility and Mortality
Key Indicators
| Indicator | India (2023 est.) | Tamil Nadu |
|---|---|---|
| Total Fertility Rate (TFR) | 2.0 | 1.7 (below replacement) |
| Infant Mortality Rate (IMR) | 28/1,000 live births | 13/1,000 |
| Maternal Mortality Rate (MMR) | 97/1,00,000 live births | 54/1,00,000 |
| Life expectancy (male) | 70.9 years | 72 years |
| Life expectancy (female) | 73.3 years | 75 years |
Replacement level fertility: TFR of 2.1 — a population neither grows nor shrinks. States below replacement: Tamil Nadu (1.7), Kerala (1.8), AP, Telangana, Karnataka, Punjab, West Bengal. States well above replacement: Bihar (3.0), UP (2.9), Meghalaya (2.9).
Demographic Transition Theory:
- Stage 1: High birth rate, high death rate → slow growth (pre-modern India)
- Stage 2: High birth rate, falling death rate → rapid growth (1950s–1980s India)
- Stage 3: Falling birth rate, low death rate → slowing growth (India now nationally; TN already in Stage 4)
- Stage 4: Low birth rate, low death rate → stable/declining population (TN, Kerala)
Tamil Nadu — Demographic Profile
| Indicator | Value (Census 2011 / NFHS-5) |
|---|---|
| Population | 7.21 crore |
| Population density | 555/sq km |
| Literacy rate | 80.09% |
| Sex ratio | 996 |
| Child sex ratio (0–6) | 943 |
| Urban population | 48.4% |
| TFR | 1.7 (below replacement) |
| IMR | 13/1,000 |
| Scheduled Caste population | 20.01% |
| Scheduled Tribe population | 1.10% |
Tamil Nadu demographics — important facts for Group I:
- Higher sex ratio (996) than national average (940) — reflects better female health and survival outcomes
- One of highest literacy states — 80% vs national 74%
- Most urbanised major state (48%) after small states/UTs
- IMR of 13 is among India's best — comparable to middle-income countries
- Below-replacement fertility means TN will face ageing population challenges in coming decades
- TN contributes ~6% of India's GDP but has ~6% of population — GDP per capita above national average
Board Exam Tips
- Census 2011: 121 crore; growth rate 17.64%; sex ratio 940; child sex ratio 914 (fell from 927 — alarming).
- Most populous: UP (19.98 crore). Highest density state: Bihar (1,106). Lowest density: Arunachal Pradesh (17).
- Most literate: Kerala (93.91%). Least literate: Bihar (61.80%).
- Best sex ratio: Kerala (1,084). Worst: Haryana (879).
- Tamil Nadu: 7.21 crore; literacy 80%; sex ratio 996; urbanisation 48.4%; IMR 13.
- India became world's most populous (surpassed China): April 2023.
- Demographic dividend window: ~2020–2041; median age 28; 12 million new workers/year.
- TFR 2.0 nationally; Tamil Nadu 1.7 (below replacement — ageing concern).
- Remittances: India = world's largest recipient ($125 billion, 2023).
- PCPNDT Act 1994/2003: bans sex determination; addresses skewed child sex ratio.