Nearly half of people in Britain said they experienced “high anxiety” as the country went into lockdown, the Office for National Statistics (ONS) says.
Anxiety levels were highest among an estimated 8.6 million people whose income fell, according to the weekly survey on the impact of coronavirus.
Renters and the self-employed were also particularly affected.
Measures of well-being were at their lowest levels since records began in 2011, the ONS said.
The survey suggested that more than 25 million people – 49.6% of over-16s in Britain – rated their anxiety as “high”, more than double the amount who did so at the end of 2019.
Those suffering the greatest level of worry were an estimated 2.6 million people who said they were struggling to pay bills.
Am I experiencing anxiety?
Most people feel anxious from time to time but if it is affecting your life then there are things you can do to help yourself and ways to seek help.
There are many symptoms, including physical ones such as headaches or a faster heartbeat, as well as mental ones, such as feeling tense or being unable to sleep, and behavioural ones, such as problems concentrating and not being able to enjoy your leisure time.
The NHS suggests ways to manage anxiety including breathing exercises, eating healthily and exercising.
More advice is available from mental health charity Mind which has published wellbeing advice for the coronavirus pandemic.
The survey data suggested that 8.6 million people had seen their income fall, with this group also reporting anxiety levels 16% higher than average.
Women reported anxiety levels 24% higher than men on average, with the ONS saying the difference might be because a larger proportion of women were either economically inactive, in lower paid jobs or working part time.
Lucy Tinkler, head of the quality of life team at the ONS, said: “All measures of personal well-being, which include anxiety and happiness, are at their worst levels since we began collecting data in 2011.”
“The most recent data showed a slight improvement in anxiety compared to previous weeks, but remained much higher than before the pandemic.”
The ONS is carrying out a weekly opinions and lifestyle survey of about 1,500 people to understand the impact of the coronavirus on Britain, and comparing it with the results of a similar survey it normally carries out monthly.
It found the average reported anxiety level rose from 2.97 out of 10 at the end of 2019 to 5.18 at the end of March as the lockdown was beginning.
In the most recent survey, from 9 April to 20 April, that fell slightly to 4.2.
The proportion of Britons reporting low happiness also rose sharply from 8.4% at the end of 2019 to 20.7% at the end of March.
Finances were the biggest worry for an estimated 5.3 million people, while 6.2 million were most concerned about their work and 8.5 million most concerned about their well-being, the survey suggested.
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