This is intentional. They're trying to make a case that Trump is a fiscal failure. (There were early positive reports, but I can't make an assessment with any certainty.) The number has been chosen as emotional charged for those which the WSJ has determined to be his base -- right wing religious folks. I think they've misplayed their hand here -- Trump was not the "religion" candidate. His supporters are more prone to chuckle at 666. Think about it: 666 billion? How can we be certain it wasn't 663? Like astronomical distances, astronomical finance is part guesswork. The fact that it devolved to a trigger number is telling.