A population pyramid is not a picture of today. It is eighty years of births and deaths stacked up, oldest on top.
Each country starts in 1945 with the pyramid it really had, and the sliders start where its birth and death rates really were. You move them one decade at a time and run the clock to 2025.
Match the target silhouette behind your pyramid. One setting held for eighty years will not match it. Change the sliders decade by decade.
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How It Works
Rules
The two sliders
Births runs from hardly any children to as many as come. It decides how wide the bottom bar is.
Deaths runs from most children dying young to almost everyone growing old. It decides how many people there are.
Migration unlocks partway through, and it runs both ways from the marked center: people leaving to the left, people arriving to the right.
Seven settings each, named in words. There is no number to hit.
The clock
Each turn advances ten years. Everyone alive moves up two rungs of the pyramid, some die, and a new bottom bar is born.
You get eight turns: 1945 to 2025. Your slider settings only affect the decade you are in.
Practice rounds
The first three countries are made up, and you can switch them off at the title screen. They score nothing.
Each one asks for one extreme shape — widest possible base, the same thing upside down, then a rectangle — and the box under the pyramid turns green when you have it.
Two things to hit
The shape. The dashed outline is the target. Get your bars onto it by 2025. That is the birth slider's job.
The size. Each level also says how full the country should end up — twice as many people, six times as many. That is the death slider's job.
You are scored on whichever went worse. Get the pattern right and you get three stars; you do not have to be exact.
The last four are marked EXPERT and they are scored tighter. Each one breaks a rule the earlier levels taught.
A miss costs you nothing but a retry, and the hint opens to show how the target set its own two sliders.
Reading a bulge
A bulge in the middle of a pyramid is a birth rate that crashed twenty-five years ago. Change the sliders now and you change the bottom bar only.
The Demographic Transition
The eighty years you just played, drawn as a curve