In the final debate, Hillary Clinton said she would secure Social Security and Medicare by raising taxes on high-income earners, including herself and her opponent, Donald J. Trump, “assuming he can’t figure out how to get out of it.”

As we’ve learned in the past few weeks, Mr. Trump has used all kinds of extravagant maneuvers to get out of paying taxes. Without Mr. Trump’s returns, we can’t know for certain whether he figured out a way to get out of paying into Medicare and Social Security. But we have some clues.

The only public information he has offered about his finances is buried in the 2015 Financial Disclosure Form 278e that he filed when he entered the Republican primary. According to his financial disclosure, Mr. Trump owns and controls an extensive business empire.

Given that, it seems incredible that he reported only $14,222 in total salary on his 2015 financial disclosure form, all of it paid by 208 Production LLC, which made his reality show “The Apprentice.” He claims that the other part of the form, which asks about “Sources of Compensation Exceeding $5,000 in a Year,” is “not applicable.”