The Trump administration likes to promote its immigration enforcement agenda through numbers, with ambitious goals to deport 1 million people, report zero releases at the U.S.-Mexico border and arrest thousands of alleged gang members.

For all the boasting, the administration has been releasing less reliable, carefully vetted data than its predecessors on a signature policy that has become one of the most contentious of Trump’s second term.

The gap in information and a loss of figures from an office that has tracked immigration data back to the 1800s have left researchers, advocates, lawyers and journalists without important statistics to hold the Republican administration to account.