https://cis.org/Catch-and-Release
According to Justice Department
data from the last five available years, around 60 to 75 percent of non-detained migrants have attended their immigration court proceedings. That’s determined by subtracting the percentage of judgments entered against migrants in their absence (known as an in absentia ruling) from total judgments entered.
But it’s worth noting that in absolute terms, that’s nearly 140,000 non-detained immigrants who were ordered to be deported between 2012-16 because they were not present in the courtroom, according to Justice Department data. (Though some immigration advocates
say that count is high.)
"On the overall question of the importance immigration officials should attach to no-shows: the glass is either half full or half empty," said Peter Margulies, an immigration law and national security law professor at Roger Williams University School of Law. Despite a majority attending their hearings, he said, "that still yields a significant number of no-shows (and) noncitizens unaccounted for."
https://www.politifact.com/punditfact/statements/2018/jun/26/wolf-blitzer/majority-undocumented-immigrants-show-court-data-s/