# 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. 