One thing is certain: the percentage of those who live alone has increased dramatically. In the US, 27% of people live alone, up from 5% in 1920, and in New York City it’s roughly one third. The same trend is evident in Canada, and even more pronounced in Europe – 58% of people in Stockholm live alone, a figure that is considered the highest in Europe. In many cities, the trend is here to stay. The Australian Bureau of Statistics estimated that there will be 1.3m more single-occupancy households by 2025, a jump of roughly 60%, and one that could crowd major cities and affect access to affordable housing.

Obscured by those figures, however, is the assumption that living alone leads to loneliness – two things the sociologist Eric Klinenberg, author of Going Solo, says are often conflated. “In fact, there’s little evidence that the rise of living alone is responsible for making us lonely,” he wrote in 2012. “Research shows that it’s the quality, not the quantity of social interactions that best predicts loneliness. What matters is not whether we live alone, but whether we feel alone.”

The demographic that most reports feeling lonely are older people, and they do often live alone. In Stockholm, 35% of people over the age of 75 experienced loneliness, while in Bristol 10-15% reported the same. (Hence the slogan “Bristol: a brilliant place to grow old.”) Older people are likely to be more lonely in cities, especially if they are poorer, have physical or mental health issues or live in underprivileged areas.