The Affordable Care Act expanded health coverage to millions of Americans in 2014. Because more people had insurance to pay for healthcare services, demand and spending predictably went up more quickly. 

But the important question for the future remains the same: Will healthcare be able to avoid large spending spikes and move to a more sustainable payment system?

“It's absolutely no surprise that 2014 had a higher rate of increase because of all the additional people getting coverage,” said Paul Ginsburg, a health economist at the University of Southern California. “The purpose of covering them was allowing them to use more services.”

The U.S. healthcare tab topped $3.03 trillion in 2014, up 5.3% from 2013, according to figures from the Office of the Actuary, an independent arm of the CMS. The data, published Wednesday in Health Affairs, differ only slightly from the projections released this past July. The amount spent on each person averaged $9,523 last year, an increase of 4.5% year over year. Healthcare represented 17.5% of the nation's gross domestic product in 2014, up from 17.3% in 2013.

The 5.3% annual growth rate was the highest since before the 2008 recession. More recently, the U.S. healthcare system recorded historically low growth in expenditures. Many observers believe the recession was a primary driver because the high rates of unemployment battered demand for healthcare services.