People identifying as white Irish, Anglo Indian or white Maltese are among the ethnic groups with the oldest average age in England and Wales, the 2021 census shows.
Japanese, Danish and white Cornish are also well above the average for the overall population.
By contrast, people identifying as mixed south Asian or mixed Pakistani/British Pakistani are among the groups with the lowest averages, at below 18 years.
A total of 287 ethnic groups in England and Wales were recorded in the census, which took place on March 21 2021.
The median age – or exact midpoint – for the overall population was 40 years.
But across the 287 groups, the median ranges from 65 years to just six, according to new analysis from the Office for National Statistics (ONS).
More than half a million (507,465) people identify as white Irish, with a median age of 54 years, one of the highest for any groups.
Nearly a third (32%) of the white Irish population are aged 65 or over, compared with nearly a fifth (19%) of the total population in England and Wales.
Other groups with a high median age include white: Cornish (47), white: Danish (47) and white: Maltese (56), as well as those in the “other ethnic group” category identifying as Caribbean (46), Greek Cypriot (47) and Japanese (49).
Top of the list are people in the “Asian, Asian British or Asian Welsh: Anglo Indian” group, comprising 2,070 residents whose median age is 65 years.
Some of the lowest median ages are in the “mixed or multiple ethnic groups” category, including black British (16 years), mixed white (15) and mixed black (13).
The category “mixed or multiple ethnic groups: Pakistani or British Pakistani” has a median age of just 11 years, as does “Asian, Asian British or Asian Welsh: mixed South Asian”.
The lowest median age of all is six years, for “mixed or multiple ethnic groups: mixed south Asian”.
Some 2,000 residents of England and Wales identified their ethnicity this way, the ONS said.