HealthAffairs attributes the rise in insurance costs largely to thehealth insurance tax, which was suspended in 2017 but went backinto effect in 2018. (Image: Shutterstock)

Health care spending grew last year but shrunk as a portion ofoverall spending.

A new analysis published in Health Affairs byMicah Hartman, a statistician in the CMS Office of the Actuary,finds that national health care spending increased by 4.6 percentin 2018 to $3.6 trillion, or 17.7 percent of the overall economy. That's down from 17.9 percentthe previous year.

One of the main drivers of the spending increase was the risingcost of insurance, which jumped 13.2 percent. That was a much moredramatic increase than in than 2017, when plan prices only went up4.3 percent.

Related: Hospital costs drive private health insurancespending

Health Affairs attributes the rise in insurance costs largely tothe health insurance tax, which was suspended in2017 but went back into effect in 2018.

The spending increase came despite roughly 1 million fewerpeople with insurance coverage. The drop in coverage was drivenlargely by attempts by the Trump administration and Congress –– inboth 2017 and 2018 –– to undermine the Affordable Care Act. Mostsignificantly, the tax law enacted at the end of 2017 eliminatedthe ACA's individual insurance mandate.

Medicare spending grew at a much faster rate, 6.4 percent, to$750 billion. While enrollment growth was typical (2.6 percent),per-enrollee expenditures rose by 3.7 percent, compared to only 1.6percent in 2017. The portion of Medicare spending on private plansincreased by over 11 percent, and now accounts for 36 percent ofoverall spending in the program.

In contrast, Medicaid spending only grew by 3 percent, reaching$597 billion. Per-enrollee spending grew by 2 percent.

One bright spot for consumers was the relatively modest growthin spending on prescription drugs: 2.5 percent. In fact, prices forretail prescriptions declined 1 percent.

Hospital spending was up 4.5 percent and spending on physiciansand clinical trials went up 4.1 percent.

Read more: 

• This is how a health care premium dollar isspent
• Hospitals must post real prices starting in2021
• Hospitals charge employers 240% more thanMedicare