Generations
The reward comes now. The consequences grow up later.
Description
Guide a fictional economy through several generations using only its birth rate. The graph is the age distribution of the living population: the present is fixed on the left, and each cohort moves right as it grows older. The vertical height is the number of people in a one-year age band. Deaths gradually lower older cohorts; the graph is not an unchanged record of historical births.
Reducing births immediately frees some adults from unpaid infant care, so GDP rises and child costs fall. Those missing babies also mean missing workers twenty years later. Existing adults keep ageing into retirement, while Social Security depends on the output and taxes of the generations behind them. Raising births creates future workers but increases current care and education costs.
Instructions
- Press Start time. About 1.8 real seconds represents one game year. Pause whenever you want to inspect the graph.
- Move the single slider to set lifetime fertility from zero to five children per woman. Actual annual births also depend on how many adults are in the childbearing ages, 20–39.
- Watch cohorts cross age 20 into working age, then age 65 into retirement. Changes in births take a full generation to change the workforce.
- Win: after Year 80, sustain at least 2.2 times starting GDP for 15 consecutive years, with debt below 120% of GDP and the combined child/pension bill below 40% of GDP.
- Lose: public debt reaches 180% of GDP, or child and pension costs reach at least 60% of GDP for three consecutive years. The campaign also ends if you have not won by Year 160.
How this economy works
The starting society has ten million residents and an older baby-boom generation. People age monthly. The illustrative mortality curve rises with age and ends at age 110; there is no immigration. Working ages are fixed at 20–64. Births are based on the slider, the ages 20–39 population, and an assumed equal sex ratio.
GDP is effective labour multiplied by productivity. The model subtracts unpaid care demands from potential labour; the current birth flow has an intentionally strong immediate effect to make the short-term temptation visible. Child costs include a one-time newborn bill plus ongoing care and education through age 19. Pension payments cover everyone age 65 and older. GDP is shown separately from those costs, not as GDP minus the care bill.
Fixed tax revenue is 35% of GDP. The public budget pays for children, pensions, basic services, and debt interest. Deficits add debt; surpluses repay it. Baseline productivity grows 1.1% annually; heavy debt and care pressure slow it. Benefits and services partly rise with productivity. Monetary amounts are constant game dollars. Rates, costs, mortality, initial cohorts, and crisis thresholds are designed for this game, not calibrated forecasts of a country. Productivity policy, migration, retirement choices, market responses, and family decisions have many real-world effects omitted here.
The demographic-dividend and ageing concepts are described by UN Population Division. The game’s instant GDP reward is an exaggerated scenario mechanic, not a universal claim about birth rates or a policy recommendation. Progress saves in this browser. Returning to the page resumes paused; switching away pauses the clock.