WASHINGTON (Reuters) – The cost of medical care in the United States is expected to grow at a faster clip over the next decade and overall health spending growth will outpace that of the gross domestic product, a U.S. government health agency said on Wednesday.

A report by the U.S. Centers for Medicare and Medicaid Services (CMS) cited the aging of the enormous baby boom generation and overall economic inflation as prime contributors to the projected increase in healthcare spending.

Overall healthcare spending will comprise 19.9 percent of the economy in 2025, up from 17.8 percent in 2015, the report forecast. The pace of growth in U.S. spending on health is expected to pick up in 2017, increasing 5.4 percent over 2016. That compares with an estimated 4.8 percent spending uptick in 2016. Spending for 2016 was estimated at $3.4 trillion.

When the final numbers are in, the growth in prescription drug spending for 2016 is expected to have slowed to 5 percent from 9 percent in 2015. However, CMS has forecast growth of 6.4 percent per year between 2017 and 2025, in part because of spending on expensive newer specialty drugs, such as for cancer and multiple sclerosis.

The projections for 2016 to 2025 were made assuming that the Affordable Care Act (ACA), former President Barack Obama’s signature healthcare law widely known as Obamacare, would remain intact. It does not take into account likely changes to the law.

The Republican-led Congress and President Donald Trump have vowed to repeal and replace the ACA, but a viable replacement plan has yet to emerge.

Trump signed an executive order on his first day in office last month to freeze regulations and enable government agencies to take other steps to weaken Obamacare.

The ACA expanded Medicaid, the government health insurance program for the poor, in more than 30 states and set up private healthcare exchanges that enabled previously uninsured people to buy health insurance. After high enrollment between 2014 and 2015, Medicaid and private health insurance spending were expected to have slowed in 2016.

But spending on Medicare, the government health insurance program for the elderly, is expected to grow between 2017 and 2025 as a larger elderly population requires more medical services.

The overall insured rate of the population is expected to reach 91.5 percent in 2025, up from 90.9 percent in 2015, the report said.

(Reporting By Yasmeen Abutaleb; Editing by Tom Brown)