Useful Data to remember while solving Estimation Problems

Let’s jump in,

  • Total world population = 7.3 billion
  • The population of India = 1.3 Billion (~18% of the world population)
    • Population of Delhi – 30 million
    • Population of Mumbai – 20 million
    • Population of Kolkata – 15 million
    • Population of Bangalore – 12 million
    • Population of Chennai – 10 million
  • Rural : Urban split = 70 : 30 = 900 : 400 million
  • Average household size in India is 4. (Urban – 3, Rural – 5)
  • Households in India = 1300 Million / 4 = 325 million
  • Households based on Rural : Urban split = 900/5 : 400/3 = 180 : 133 million
  • Male : Female ratio in India = 50 : 50 % = ~ 650 million each.
  • Male : Female ratio in world = 50 : 50 % = ~ 3.65 billion each.
  • Population of Married / Others = 50% = 650 million
  • Population of Never Married = 50% = 650 million

  • Age groups in India 
    • 0 – 14 = 30% = 390 million
    • 15 – 35 = 40% = 520 million
    • 35 – 60 = 25% = 325 million
    • 60+ = 5% = 65 million
  • Income Groups in India 
    • Poor = 20% = 260 million
    • Low = 75% = 975 million
    • Middle = 3.5% = 45 million
    • Upper Middle = 1% = 13 million
    • High = 0.5% = 6.5 million
  • Number of Pincodes in India = ~20,000
  • Smartphone users in India = 60% = 800 million
  • Internet penetration in India = 50% = 625 million
  • Below Poverty Line in India = 15%
  • Births per year in India = 25 million. (of which 1/3rd dies = 8M)

  • Population Density of 
    • India = 400 / km sq.
    • Kolkata = 25,000 / km sq.
    • Mumbai = 32,000 / km sq.
    • Delhi = 20,000 / km sq.
  • Population by Continents 
    • Asia – 60% = 4.3 billion
    • Africa – 15% = 1.1 billion
    • Europe – 10% = 730 million
    • Latin America – 10% = 730 million
    • North America – 5% = 365 million
  • Age Groups (World) 
    • 0-5 years = 10% = 730 million
    • 6 – 14 years = 20% = 1.46 billion
    • 15 – 35 years = 40% = 2.9 billion
    • 36 – 60 years = 20% = 1.46 billion
    • 60+ = 10% = 730 million

  • Income Group (World) 
    • Poor (<$2) – 15% = 1.1 billion
    • Low ($2 – $10) – 55% = 4 billion
    • Middle ($10 – $20) – 15% = 1.1 billion
    • Upper Middle ($20 – $50) – 10% = 730 million
    • High ($50+) – 5% = 365 million
  • Number of smartphone users in the world = 4 billion.

Toufiq Mahmud