A Trump administration attorney said Monday that the numbers used for deciding how many congressional seats each state gets won’t be ready until mid-February at the earliest.

John Coghlan, a deputy assistant Attorney General, said during a court hearing that the U.S. Census Bureau had found new irregularities in the head count data that determines congressional seat allocations and the distribution of $1.5 trillion in federal spending each year.

Under federal law, the Census Bureau is required to turn in the apportionment numbers by Dec. 31, but the bureau announced last week that the numbers wouldn’t be ready. At the time, the Census Bureau said it would finish the apportionment numbers in early January, as close to the Dec. 31 deadline as possible.