Amid steady progress with coronavirus vaccinations, the U.S. economy is gathering so much steam that its gains will not stay at home. Demand for goods and services this year is expected to spill well beyond U.S. borders, making the United States the largest single contributor to global growth for the first time since 2005, according to Oxford Economics.

The U.S. ascent ends — at least for now — China’s long reign as the principal engine powering the $90 trillion global economy.

Free spending by the Biden administration — coupled with the Federal Reserve’s ultralow interest rates — is driving the nascent U.S. boom and lifting other countries, where governments have not responded as aggressively to the pandemic. As Americans spent their $600 government stimulus checks in January on furniture, laptops and clothing, the U.S. imported a record $221 billion worth of goods. And that was before a round of $1,400 checks in March.

“We are ahead of the world,” said Kristin Forbes, who was one of President George W. Bush’s White House economic advisers. “And a meaningful share of the stimulus is likely to leak abroad.”