After years of steady decline, the number of U.S. children without health insurance rose by 276,000 in 2017, according to a Georgetown University report released Thursday.

While not a big jump statistically — the share of uninsured kids rose to 5 percent in 2017 from 4.7 percent a year earlier — it is still striking. The uninsured rate typically remains stable or drops during times of economic growth. In September, the U.S. unemployment rate hit its lowest level since 1969.

“The nation is going backwards on insuring kids and it is likely to get worse,” said Joan Alker, co-author of the study and executive director of Georgetown’s Center for Children and Families.

Alker and other child health advocates place the blame for this change on the Trump administration and the Republican-controlled Congress, saying their policies and actions cast a pall on enrollment.

The number of children without coverage rose to 3.9 million in 2017 from about 3.6 million a year earlier, according to census data analyzed by Georgetown.

The overall uninsured rate for people of all ages — which plummeted from 2013 to 2016 following the health law’s implementation — remained unchanged at 8.8 percent last year.

The share of children with employer-sponsored coverage rose modestly in 2017, but not by enough to make up for the drop in children enrolling in Medicaid or getting coverage from Obamacare insurance exchanges, Alker said.

While no states made any significant gains in lowering children’s uninsured rate, nine states experienced significant increases. The biggest occurred in South Dakota (up from 4.7 percent to 6.2 percent), Utah (up from 6 percent to 7.3 percent) and Texas (from 9.8 percent to 10.7 percent).

More than 1 in 5 uninsured children nationwide live in Texas — about 835,000 kids — by far the highest number of any state.

Florida had 325,000 uninsured children last year, as its uninsured rate for that age group rose 0.7 percentage points to 7.3 percent. California had 301,000 children without insurance, though its number remained virtually unchanged, relative to the previous year.

Other states with significant increases were Georgia, South Carolina, Ohio, Tennessee and Massachusetts.

The uninsured rates for children increased at nearly triple the rates in states that did not expand Medicaid under the Affordable Care Act, according to the report. Studies have shown that children whose parents are insured are more likely to have coverage.

The uninsured rate among Hispanic children was 7.8 percent, compared with 4.9 percent among whites and 4.6 percent among blacks overall. (Hispanics can be of any race.)

Georgetown has been tracking these figures since 2008 when 7.6 million children — or about 10 percent of kids — lacked health coverage.

Because nearly all low-income children are eligible for Medicaid or the federal Children’s Health Insurance Program, known as CHIP, the challenge is making sure parents are aware of the programs, getting them enrolled and keeping them signed up as long as they are eligible, Alker said.

Congress let the CHIP program funding lapse for several months in 2017, putting states in a position of having to warn consumers that they would soon have to freeze enrollment. Congress restored federal funding in early in 2018.

In addition, low-income families were bombarded by news reports last year of Congress threatening to repeal the health law that expanded coverage to millions. In the past two years, the Trump administration has slashed funding to Obamacare navigators to help people sign up for coverage.

Alker also pointed to the Trump administration’s September proposal, known as the “public charge” rule, which could make it harder for legal immigrants to get green cards if they have received certain kinds of public assistance — including Medicaid, food stamps and housing subsidies. Green cards allow them to live and work permanently in the United States.

OLE Health, a large health provider based in Napa Valley, California, that serves many immigrants, said it has seen patients disenroll from Medicaid in the past year. CEO Alicia Hardy said many have dropped coverage over fears the help could jeopardize their immigration status.

“They are afraid of being deported,” she said.

All those events could have deterred families from getting their kids covered. “The welcome mat has been pulled back and as a result we see more uninsured children,” Alker said.

She said the easiest way to change the trend would be for more states to expand Medicaid under the health law. Fourteen states have yet to do so. Though the expansion largely affects adults, as parents enroll, their children are likely to follow.