According to figures published last week by the Office for National Statistics (ONS), the number of people on zero-hours contracts has increased by a fifth compared to a year ago.

The ONS statistics show that in April to June this year, there were 903,000 people employed on zero-hours contracts compared to 747,000 in the same period in 2015 – an increase of almost 21 per cent. Overall, the ONS estimates that 2.9 per cent of people in employment are now on zero hours compared to 2.4 per cent in 2015.

In terms of age, 8.4 per cent of workers aged 16 to 24 are now employed on zero hours, compared to 6.7 per cent a year ago; while only 1.6 per cent of workers aged between 35 and 49 are estimated to be on zero-hours contracts compared to 1.5 per cent in the same period in 2015.

Far more women than men are employed on these contracts, with 3.4 per cent on zero hours in April to June 2016 (2.8 per cent in 2015) compared to 2.4 per cent of men (2.1 per cent in 2015). Overall, women make up 55 per cent of those estimated to be working on zero-hours contracts.

In terms of regions, the East Midlands has the highest percentage of people on zero-hours contracts. In April to June 2016, 3.6 per cent of workers in the region were estimated to be employed on these contracts compared to 2.9 per cent a year ago. Northern Ireland has the lowest recorded percentage at 1.9 per cent.

Almost a quarter of people in the accommodation and food sector are employed on zero-hours contracts (24.7 per cent) in 2016, compared to 23.2 per cent in 2015. By contrast only 2.1 per cent of people employed in construction are employed on these contracts (3.9 per cent in 2015).

Iain Birrell, of Thompsons Solicitors, said: “Concern around the gig economy is growing, and these figures show that it is right that these issues are raised. The headlines have been grabbed in relation to a few employers such as Sports Direct and Deliveroo, but they can distract from the scale of the issue.

“As solutions go one size will not fit all, there are some workers for whom a gig economy is a welcome thing. They are in the small minority however. The research shows that countries do not prosper where high levels of job insecurity are present and zero hours contracts are insecure. A general growth of them is a deeply concerning trend.”

To read the statistics (which are calculated from responses to the Labour Force Survey) in more detail, go to: https://www.ons.gov.uk/employmentandlabourmarket/peopleinwork/earningsandworkinghours/datasets/zerohourssummarydatatables