Population

Population is how many people live in a system, counted in points. A new colony starts with 15.8 population.

How it grows

Population moves toward a growth target. It grows fast at first, then slows down as it gets close.

With no extra stability, the colony stops below its target. Every point of population lowers stability for as long as it stays, so growth stops when stability runs out. See stability. At 0 stability or below, the system also gets a Population status that reduces its outputs.

What sets the speed

• Housing sets the target: housing + 0.75. A system above its target shrinks back toward it, faster at high stability. See housing.
• Stability speeds growth, up to 25 stability. More than 25 adds nothing.
• Negative stability makes population slowly drop, whatever the housing. Below −10 stability, it drops twice as fast.
• Size slows growth down. At 120 population or more, a system grows at a fifth of the speed of an empty one.

Here is the exact growth, for players who want it:

stability below −10:  growth = -0.002 population per tick-0.04 population per hour
stability below 0:    growth = -0.001 population per tick-0.02 population per hour
otherwise:            growth = (base + min(stability, 25) × 0.002 population per tick0.04 population per hour) × housing factor × size factor

base           = 0.02 population per tick0.4 population per hour
housing factor = min((housing + 0.75 − population) × 0.1, 1)
size factor    = (1 − min(population, 120) ÷ 120) × 0.8 + 0.2

What population gives

• Taxes in credits.
• A stability cost: every point lowers stability for as long as it stays. See stability.
• In a system you own, population adds defense. See defense.

Taxes, the stability cost and defense count only whole points of population. That rounded-down number is the system's workforce. Growth uses the exact value, fractions included.

A Navarch's conquest, bombardment or pillage can kill part of a system's population.