Use case 03
Migration & population. Who will live here in twenty years?
Schools, clinics, transport and housing are planned decades ahead, but populations move. A population twin follows births, ageing, internal movement and migration at regional level and shows a range of futures.
Photo: Frankie Fantopoulos · Pexels License01 · The questions
Population forecasting for Greece. The questions planners ask.
Population forecasting matters most where services are planned decades ahead: schools, clinics, transport and housing. These are the kinds of questions a population twin would explore for Greek regions and islands. The answer is a range of futures, not one number.
Which regions could face a shortage of working-age residents?
How do seasonal and permanent populations differ, and what does that mean for services?
02 · What the twin would model
Migration forecasting. What the twin would model.
Migration forecasting and population projections start from the same building blocks: births, deaths, age structure and movement between places. A population twin adds the housing, jobs and services that pull people in or push them out, region by region. We work with aggregate statistics only.
Layers
03 · Audience
Population projections for planning. Who it is for.
This twin is meant for people who plan services for a population that is ageing and moving, from Greek islands to whole regions. It starts from official statistics, such as the census and Eurostat projections, read as ranges rather than certainties.
- Regional and municipal planners
- Ministries
- Demographers
- Universities
- NGOs
04 · Public sources
Public sources we plan to start from.
We plan to start from open public data and add partner data only with clear agreements. For each dataset we record where it came from, when it was updated and what its limits are.
Listing a source does not mean we have a partnership with it. These are public datasets we plan to evaluate.
05 · Research
From our research.
Background reading from our research notes, with a source for every claim. These articles explain the public data and the methods behind this use case.
Population
Greece's population in 2026: the decline in official numbers and projections
Greece population in 2026: the 2021 census counted 10.48 million, 3.1% fewer than 2011. What Eurostat projects for 2050 and 2100, and what ageing means.
2026-11-04 · 6 min read
Methods
Agent-based models, explained, and how to use them without profiling people
What an agent based model is, from Schelling's segregation model to epidemic and evacuation simulations, and how to build one on aggregate data.
2026-11-04 · 6 min read
06 · Questions
Migration & population. Frequently asked questions.
Short answers to common questions, based on the public sources cited on this site. If yours is missing, write to us.
What will Greece's population be in 2050?
In Eurostat's EUROPOP2025 baseline, Greece has about 9.18 million people in 2050, down from about 10.37 million in 2025. Eurostat stresses that these are "what-if" projections, not forecasts. People aged 65 and over would rise from about 24% to about 35% of the population. Migration is the big unknown, as our Greece population post explains.
What causes Greece's demographic decline?
Low fertility is a large part of it: Eurostat puts Greece's total fertility rate at 1.24 children per woman in 2024, below the EU figure of 1.34. The population is also ageing, and movement within the country matters: only two of the thirteen regions grew between the 2011 and 2021 censuses. Migration into and out of the country can widen or narrow the gap.
Can policy reverse population decline?
We do not judge specific policies. What the official figures show is how much the outcome depends on assumptions: for 2100, Eurostat's sensitivity tests range from about 5.13 million with no migration to about 8.43 million with higher migration. A population twin would let planners test how school, health and housing needs change under several paths, rather than betting on one.
What is Greece's population now?
The latest census, with a reference date of 22 October 2021, counted 10,482,487 residents, 3.1% fewer than in 2011. ELSTAT runs a census every ten years. Eurostat's latest projections start from about 10.37 million on 1 January 2025. The census and the projection use different dates and methods, so the two totals are not directly comparable.
How does migration and population forecasting work?
Both start from the same building blocks: births, deaths, age structure and movement between places. A population twin adds the housing, jobs and services that pull people in or push them out, region by region. The result is a range of possible futures, not one number. We work with aggregate statistics only and never track individual people.
07 · Other use cases
Other use cases.
Every twin starts from a specific question asked by a real user. These are the other areas we are starting with.
Early access
Want to pilot this use case?
Tell us what you would like to model. Pilot partners help decide what we build first.
Concept stage. No product is live yet.