In March 2025, the global population reached 8.21 billion. But Finnish researchers say Earth may be more densely populated than we thought.
A new study finds that statistics significantly underestimate rural populations. The problem, the team says, is the widely used grid method for counting people: divide a territory into squares and estimate each square’s population from census data.
But those estimates were calibrated mostly in urban areas, so errors in rural counts have gone unnoticed.
What Did the Scientists Report?
Rural areas are home to 43 percent of the world’s population. If the team’s calculations are right, the number of people missing from statistics could reach billions.
‘We are the first to provide evidence that a significant portion of rural residents may be missing from global population datasets. We were surprised to find that the actual number of people living in rural areas is much higher than what global data suggests. Depending on the dataset, the rural population is underestimated by 53 to 84 percent,’ said Dr. Yozias Lang-Ritter, a co-author of the study.
The team analyzed population data from 1975 to 2010, focusing on how dam construction displaced people — a case where on-site counts are usually available, Science Alert reported.
They looked at 307 dam projects in 35 countries, comparing official counts of displaced people with estimates from five major population datasets.
The researchers say the gap stems from a lack of detailed rural data — everything from up-to-date censuses to healthcare and infrastructure records.
‘The results are striking, as these datasets have been used in thousands of studies and widely relied upon for decision-making, yet their accuracy has not been systematically assessed,’ said Dr. Lang-Ritter.
Not everyone agrees. Some outside researchers argue that better satellite imagery and data collection have narrowed these gaps.
Even if the error isn’t as large as the team claims, it could still mean hundreds of millions of people are miscounted.
Accurate population estimates matter for everything from public services to climate-impact planning. The team says we need better ways to track rural populations — people shouldn’t be overlooked and miss out on vital resources.
The study appears in the journal Nature Communications.
