SPRINGFIELD, Ill. (NEXSTAR) — The U.S. Census Bureau officially confirmed Illinois will lose one seat in Congress for the next ten years in a press conference on Monday afternoon.

Illinois has 18 seats in Congress now, down from 19 in the 2010s. Democrats in the state legislature, who hold a supermajority in both the House and Senate, are already in the process of drawing the new maps that will divide voters into 17 congressional districts in 2020.

A total of 13 states saw their apportionment change, altering which states gained or lost seats in the U.S. House of Representatives. Texas saw the largest gain with two new seats on The Hill.

Federal officials said the data state legislatures use for redistricting should be released by September 30th, which delays Illinois’ efforts to draw the new political maps before one of the deadlines in the state constitution.

At a separate press conference in Aurora on Monday morning, Governor Pritzker blamed the state’s long-running population decline on college students moving out of state.

“Actually, the largest portion of the population that was moving out were young people who were choosing to go to college out of state, because they couldn’t afford to go to college,” Pritzker said.

“I’m concerned about it,” the governor said. “I will say that, you know, over a decade, we’ve lost population. We’ve got to turn that around.”

West Virginia, Pennsylvania, New York, Ohio, California, Ohio, and Michigan were the other states to each lose a seat in Congress. Demographic statisticians at the U.S. Census Bureau said New York was next in line for a seat, but came just 89 people shy of keeping a seat in Congress. That 435th and final seat in Congress went to Minnesota instead.

Florida, Montana, North Carolina, and Oregon each gained a seat in Congress.

Bordering states Indiana and Iowa saw 4.7% population growth over the last decade. Kentucky grew 3.8%. Wisconsin registered a 3.6% increase in population over the last decade. Missouri added 2.8% to its population base.

Illinois held 27 seats in Congress in the 1930s, but has continually lost seats as population here has either declined or fell behind growth in other states.

This story has been updated to include more specific population data from the U.S. Census Bureau.