Giving all Americans a guaranteed salary would boost the economy permanently, a new study has found.

The study, conducted by the Roosevelt Institute, a left-leaning think tank, looks into how a universal basic income (UBI) would impact the American economy.

In such a society, each citizen is entitled to a basic income, which would come in the form of a monthly check. That check would likely not be the person's primary income, but it would establish a basic standard of living, and provide security for those who find themselves out of work.

A new study from the Roosevelt Institute has found that instituting a universal basic income could permanently grow the U.S.'s GDP. It studied three possible UBI's, one where adults were given $1,000 a month (bottom), one where adults were given $500 a month (center), and one where kids were given $250 a month (top)

The idea has been gaining traction in recent years, and has such famous backers as Facebook's Mark Zuckerberg, Virgin's Richard Brandon and Tesla's Elon Musk.

Silicon Valley is especially interested in the idea since their innovations in technology have been leading to automation in manufacturing and other fields, causing a loss in jobs.

While the economists behind the Roosevelt Institute study believe that a basic income would be positive, the idea has many critics who believe that UBI actually discourages work and is too expensive to keep going in the long term.

This new study paints a more positive image for how UPI would impact the economy.

It tested three models of UBI, one where each adult was given $1,000 a month (a $12,000 a year salary), one where each adult was given $500 a month (a $6,000 a year salary), and one where each child was given $250 a month (a $3,000 a year stipend).

If paid for by increasing the federal debt (as opposed to raising the money through taxes), each model boosted the economy for about eight years and then flattened out, but nevertheless increased the GDP permanently.

The model that gives each citizen $1,000 a month would grow the economy by 12.56 to 13.10 per cent by 2025 before leveling off. It would also increase employment by 2 per cent and expand labor force to 4.5 to 4.7 million people.

If the UBI is paid for with taxes, it has effect on the economy.

'In effect, it gives to households with one hand what it is takes away with the other,' the researchers wrote.

However, one of the models tests how a tax-funded UBI would impact the economy, if lower-income households were taxed less than higher-income households. In this scenario, the economy would grow.

The researchers explain that the economy grows in this situation because poorer people are more inclined to spend their money than hold onto it.

Of course this is all theoretical, but the researchers say that the model they are using, run by Bard College's Levy Economics Institute, uses more realistic assumptions about the economy than other models.

While UBI is being studied at think tanks and universities around the world, it's also being put to real practice in Finland.

A trial is currently taking place on a small scale in the Scandinavian country, where 2,000 unemployed people are being given a guaranteed income of about $664 dollars a month. That amount is paid even if the trial participants find work. So far, the study has found that participants have lower levels of stress and report feeling a greater incentive to find work and freedom to pursue entrepreneurial ideas.