Demographics
Every land province has a resident population that grows or shrinks each month. Population drives economic output, military manpower and political weight, and its growth follows a modelled demographic transition shaped by health, education, urbanization and policy.
Every land province on the The Map holds a resident population, and a country's population is simply the sum of the provinces it owns. Population is not a decorative statistic: it is the workforce behind a province's Economic Output, the pool that national Manpower is drawn from, and the electorate that gives a province its weight in Elections and Politics.
Population changes once a month. Natural growth is the main force, calculated per province from a handful of social indicators. On top of it come war losses, Famine, Devastation, the province's terrain and archetype, and national policies. A planned second system, Migration, would also move people between provinces; it is not yet in the game.
What population does
- Economy. A province's people are its workforce. Its output and GDP per capita determine the tax base and, through GDP per capita, how urban the province becomes.
- Military. A fixed share of the population not under enemy Occupation sets the country's manpower ceiling, which every brigade is trained and reinforced from.
- Politics. A country's popular support is the population-weighted average of its provinces, so large provinces decide elections. Country-wide figures such as Education and Unrest are also population-weighted.
Natural growth: the demographic transition
Each month every province grows at a rate derived from an annual figure. The model reproduces the demographic transition that real societies went through after the war: a rural, unschooled society with poor health grows fast (around 2% a year), while an urban, educated European society grows at 0.5–1% a year. The 1946 settings were fitted to how countries actually grew between 1946 and 1960.
Five inputs are measured for every province:
| Input | Where it comes from | Effect on growth |
|---|---|---|
| Economic satisfaction | The owning government's support | Confidence raises births and hardship lowers them. The effect scales with education: downturns weigh on educated societies far more than on agrarian ones. |
| Education | The province's own Education level | Higher education lowers fertility, by up to 2 percentage points a year at full attainment. |
| Public health | A baseline, raised by healthcare law and research | Poor health costs up to 1 point a year; good health adds at most 0.2. See Public Health. |
| Gender equality | A baseline, moved by the Women's Rights law | Wider participation of women in education and work steadies birth rates lower, in proportion to education. |
| Urbanization | The province's GDP per capita | The strongest single brake: a fully urban province grows about 1.8 points a year slower. See Urbanization. |
The starting point is a baseline of 2.2% a year, from which each factor adds or subtracts. Because the factors interact (economic mood and gender equality both matter more in educated societies), the same policy can have quite different demographic consequences in different countries.
Development slows growth
The practical upshot is that modernization pays a demographic price. Mass education, better healthcare and a richer, more urban economy all raise output and research speed, but most of them eventually slow population growth. Medicine is the exception in poor countries: raising health from a low level cuts mortality and speeds growth, which is why health research does the most where people die youngest.
The Baby Boom
The United States, Canada, Australia and New Zealand carry a Postwar Baby Boom national modifier from 1946 to 1964, adding 1.6 percentage points to annual growth while it lasts.
Other influences on population
- Policies and focuses. National laws and focuses grant Population Growth directly. Family policy pays for it (Child Allowances and Comprehensive Family Support each add a little), healthcare systems from Social Health Insurance upward add a small amount, and the Women's Rights law trades gender equality against growth.
- War. Soldiers killed in battle are removed from their country's population each month, spread across its provinces in proportion to their size. Each day of battle also kills civilians in the contested province, and the Devastation it leaves slows the province's growth until it recovers. See Wars.
- Famine. A Famine removes part of a province's population at once. Research such as Precision Irrigation lowers the chance; Cold Chain Distribution lowers the loss.
- Terrain. Every land province has a terrain type, and each terrain adds or subtracts a small annual adjustment.
- Archetypes. Some provinces carry an archetype describing a lasting specialization. The Regional Center archetype, a hub town drawing people from the countryside, grows a little faster than the region around it. See Provincial Economy.
- Organizations and regions. Membership effects from International Organizations and modifiers held by a region can also add growth.
Reading population in the game
The province view shows the current population; hovering it summarizes the projected annual growth. The Population Growth figure (for example +1.85%/yr) has a tooltip breaking the rate into each part of the demographic model, devastation, national policy and organization modifiers, terrain, archetype and regional conditions. Economic Satisfaction sits beside it, with its own breakdown of how it affects births and calms Unrest.
At the country level, clicking the population figure opens its monthly history and a list of provinces ordered by size. The Population map mode shades every province by head-count.
Related mechanics
- Manpower – how population becomes soldiers.
- Education, Public Health and Urbanization – the inputs of the growth model.
- Migration – the planned system for moving people between provinces.
- Famine and Devastation – the sudden shocks.