It's Janet Yellen's last week running the Federal Reserve.
On today's show, we focus on a single speech Yellen gave last year.
In the speech, Yellen lays out one of the most baffling mysteries in the American economy right now.
Also, the speech reveals a certain boldness that Yellen brought to the job. Superficially, it looks like one more speech about monetary policy. But look a little deeper and you see Yellen is asking some radical questions.