NI has highest percentage of young adults still living with their parents
Northern Ireland has the highest percentage of young adults living with their parents, according to Office for National Statistics figures.
The figure of 35.3% of people aged between 20 and 34 was the highest in the UK in 2011.
In contrast, London had the lowest proportion, at 19.7%.
The ONS said the size of Northern Ireland meant it was more feasible to commute to work or university and remain at the parental home.
It said another factor was "the prevalence of cohabitation in Northern Ireland is around half of that observed in the rest of the UK".
"Conversely, the average age at first marriage in Northern Ireland is around a year lower than in England and Wales.
"These factors paint a more traditional picture of families in Northern Ireland, whereby young adults move out of the parental home later, cohabit less and marry earlier than in the rest of the UK.
"In other words, the time between leaving home and marrying may be shorter in Northern Ireland than elsewhere."
The ONS report, Young adults living with parents in the UK , said London's low figure was because it "has a large influx of young adults from other areas of the UK and from abroad due to increased employment and study opportunities".
"Sharing a household with friends or housemates is more common among young adults and migrants than older adults as a way of reducing the cost of housing.
"In 2011 in London, 6.8% of households consisted of two or more people who were unrelated, more than double the national average of 3.2%.
"The average (median) age of people living in such households in the UK was 25."