David Letterman picked the worst time to retire.

With Donald Trump's presidential bid quickly becoming the gift that keeps on giving for late-night comedians, the former Late Show host made a special appearance over the weekend to deliver a special Trump-themed Top 10 list.

Letterman, whose last Late Show episode aired back in May, came out of retirement Friday night to appear as a surprise guest on Martin Short and Steve Martin's A Very Stupid Conversation comedy show in San Antonio, Texas. He told the audience that retiring just before Trump announced his presidential candidacy was "the biggest mistake of my life."

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"I had no regrets. None. I was happy," he noted. "I was complacent, I was satisfied, I was content. And then a couple of days ago Donald Trump said he was running for president."

Among the "Top 10 interesting facts about Donald Trump" that Letterman shared? "If president, instead of pardoning a turkey on Thanksgiving, he plans to evict a family on Thanksgiving."

Check out a fan-shot video of Letterman's appearance here: