![Marketplace show](https://d3dthqtvwic6y7.cloudfront.net/podcast-covers/000/026/804/small/apm-marketplace.jpg)
Summary: <p>… But those tweets do affect markets, and JPMorgan is launching a new index to track the impact of a presidential tweet. Plus: dispatches from the supposed “worst place to live in America,” and is bigger still better for American companies?</p>