How 1in8b works
1in8b is built on real statistics. Here is how it decides where you are born and what happens in each year of your life.
Your birth
Your country or region is drawn by its real share of the world’s births in 2023 (UN World Population Prospects 2024), across 194 places. Your sex follows the sex ratio at birth there. Your family’s income rank comes from that country’s income distribution, and city or countryside from its urban share.
Each year
Every year, the chance of dying comes from the life table for your age, sex and country. How far you go in school follows the country’s completion rates, and children from richer families tend to go further. Work, earnings, the age people marry and the number of children follow national figures from the World Bank and the ILO.
Your choices
Decision cards (study harder, move to the city, take a job, have a child) change the odds, but they cannot remove the statistics of where you were born. On Auto, the game decides neutrally, so lives on Auto match the national averages. Automated tests check this against the source data for life expectancy, schooling, marriage and children.
Money
Money follows simple game rules built on each country’s incomes, worked out in dollars at purchasing power parity and shown in the money of the country where the life is lived, at its prices. Families in the poorest fifth spend 95% of their pay and the richest fifth 70%; each child under 18 adds a tenth, up to 30%, but a family does not borrow for daily needs. What is left is saved at 2% a year. Savings are spent too: each year 4% of what is above one year’s pay, and in old age they are spread over the years left until 95. Weddings, illness, harvests, theft and other events cost or bring money, and a shortfall becomes debt: 12% a year where income per head is under $10,000, 6% elsewhere, and nobody lends more than two years’ pay. Someone keeping the home for a partner, or under 30, out of work and living with parents, is kept by the household. Workers in formal jobs get a pension of 40% of their last pay; others live on their savings and then on help from their children. What is left at death goes to the children, or else to the partner.
Is it real data?
The odds and averages are real. The people, names and events are made up from them. Events based on a statistic are marked in your life record. Where the World Bank has no figure for a place, we use the median of similar countries and mark it as an estimate.
Sources
UN World Population Prospects 2024: births, life tables, fertility, sex ratio. World Bank World Development Indicators: income, inequality, schooling, urban share, health spending. ILO: labour force and work. Latest year available for each figure. WHO Global Health Estimates 2021: causes of death by country, age and sex. Pew Research Center 2020: the religious make-up of each country. World Bank: purchasing power parity rates (ICP 2021 for Taiwan), to show money in the currency of the country where the life is lived.