Downderry is a village of owner-occupiers who have already done the difficult part of their working lives. Four in five own their homes. Half the residents are over 55. A third of households contain one person, and families with children are the minority. Nobody arrives here to find themselves. They arrive having already decided.
Tenure is about as settled as English housing gets. Census 2021, which is the source for the population figures throughout this answer, puts owner-occupation at about 80%, private renting at about 15% and social renting at about 5%. A rental market that small is not really a market: it is whatever happens to be free when somebody asks.
The age profile explains most of the rest. The median age is 55, and only about 16% of residents fall in the 25 to 44 band, which is the stretch of life where people are usually building careers, having children and moving twice a decade. That group is thin on the ground here, and everything from the school run to the pub trade follows from it.
Household income runs at about £54,600 a year, gross and before tax. That figure is modelled for the financial year to March 2023, so it describes a year that has already closed rather than what anyone is earning this month, and it should be read as the shape of local incomes rather than a live salary check.
Family households are the exception rather than the rule. Lone-parent households account for about 5% of the total, and couples with children about 14%. In most villages that combination would raise questions about the primary school roll. Here it simply describes the place.
The full household make-up puts single-person households at about 33%, of which single pensioners are about 19%, and those two figures should never be added together because the second sits inside the first. What that leaves is a village weighted towards people living alone or in couples, with the classic two-adults-and-two-children arrangement running well behind.
On education, about 45% of residents hold a degree-level qualification and about 11% hold none at all, with full-time students at roughly 0.8%. That is a mixed picture rather than a uniform one, and it says nothing about anything else on this page.
Health self-reports are decent: about 81% of residents describe their health as good or very good, and about 5% as bad or very bad. Widening out to the council area, which is a different geography and covers all of Cornwall, adult smoking runs at about 12% and is classed as similar to England, and the preventable mortality rate is also classed as similar to England. Those are county-level benchmarks and belong to the county, not to this village's residents.
The population here is middling in the plainest sense: comfortable, settled, older than the country at large, and neither the reason to buy nor the reason to walk away. The one thing worth planning around is that the age curve here is not going to reverse itself for your convenience.