The US economy expanded faster than initially anticipated in the years between 2021 and 2023, according to an annual update of government data released Thursday.

The performance of the world's biggest economy has become a key factor for voters as the United States gears up for its presidential election in November.

Americans have been feeling the pinch from higher costs of living in recent years even as inflation has cooled, and this could affect the way they assess the current Democratic administration as they head to the polls.

GDP growth was 2.9 percent for 2023, up from a previously estimated figure of 2.5 percent, said the Commerce Department.

Growth for 2022 was also lifted, from 1.9 percent to 2.5 percent, the department added.

Both changes mainly reflected upward revisions to consumer spending and business investments.

Better consumer spending than expected meant that GDP growth was revised slightly upwards for 2021 too, while the decrease in GDP in 2020 was unchanged.

But the broader picture of the economy remains "little changed" from earlier estimates, said the Commerce Department.

The annual revisions show that the US economy "grew even stronger than previously thought in recent years and reaffirm that recent performance has been solid as well," said Michael Pearce, deputy chief economist at Oxford Economics.

"The recovery is built on strong foundations, with incomes growth revised significantly higher and productivity growth faster than previously presumed," he added.

Pearce expects the US economy will continue growing in the coming year, and that labor market conditions are not likely to worsen markedly from here.

A separate government report released Thursday, meanwhile, showed that GDP growth in the second quarter this year was not changed -- remaining at an annual rate of 3.0 percent.

But the rate for the first quarter was revised slightly higher to 1.6 percent, noted the Department of Commerce.