There was little growth in the pool of affordable homes for rent in Dorset last year, new figures reveal.

Think tank the Smith Institute says the national supply of affordable properties across England is increasing nowhere near quickly enough.

It warns renters are being pushed into the pricier and more insecure private market while the Covid-19 pandemic is making many people’s lives more precarious.

Ministry of Housing, Communities and Local Government data shows there were 23,521 social and affordable homes in Dorset in April last year – up just 0.3% from 12 months earlier.

This was broadly in line with the rise across England as a whole, where the figure rose by just 0.4% to 4.15 million – an extra 17,000 homes.

The Smith Institute, which set up the Affordable Housing Commission to review housing affordability across the country, said the increase fell far short of what was required.

It added that the MHCLG data does not distinguish between affordable rent – set at up to 80% of market value – and cheaper social rent, which is pegged to local incomes.

The group estimates the Government needs to build 90,000 social rent homes a year to meet demand.

The institute’s deputy director Paul Hunter said: “With the loss of stock due to right to buy, demolitions and the conversion of homes to more expensive but so-called affordable rent, the supply of social rented housing is actually in decline.

“The current economic fallout from the coronavirus pandemic looks set to demonstrate the cost of this failure. The lack of social housing means low-income households are now more reliant on the private rented sector, where rents are higher and tenancies less secure.”

In Dorset, 11% of homes were social or affordable in 2019 – below the national average of 17%.

Separate MHCLG figures show that the percentage of England’s homes which were social or affordable dropped from 20% in 2001 to 17% last year, while the share of the market occupied by the private rent sector almost doubled over the period.

Polly Neate, chief executive of the housing charity Shelter, said: “Thousands of families have spent the lockdown in shoddy, overcrowded temporary accommodation. And many more are in expensive, insecure private rentals desperately worried about paying the rent as incomes are hit. The pandemic has shown, more than ever, the importance of a safe, stable home.”

An MHCLG spokesman said: “We’ve delivered more than 460,000 affordable homes since 2010, including over 331,800 affordable homes for rent, and we’re investing £12 billion to build affordable homes in the next five years – the biggest cash investment in affordable housing for a decade.”