Changes of monthly age-adjusted mortality before and after earliest month of retirement between treatment and control counties
Notes: The figure shows the differences in the age-adjusted mortality rates between treated and control counties over time. In the upper graph, the solid line represents the treated counties and the dashed line represents the control counties. The lower graph plots the differences. December 2011 is the month when Watts Bar Fossil Plant in Tennessee shut down. The other four coal power plants shut down later (see Table 1). This figure shows that the age-adjusted mortality rate in the treated counties after the retirement of a nearby power plant was lower, while the mortality rate in the control cities was similar over time.