Biden tax plan defines wealthy at $400,000 per year or more—Is that the Goldilocks number?
Joe Biden has drawn the dividing line between "the rich" and everyone else at $400,000 for his proposed tax plan. Economists on the left say the bar should be set lower to raise more revenue. Others say it should be higher, especially to help merely affluent families in the Northeast and California. CNBC's Robert Frank takes a at what number should define "rich" in the tax debate.