Are We #StayingHome to Flatten the Curve?

The spread of COVID-19 across the U.S. in the months since January 2020 and the worry of an impending strain on the medical system led to concerted efforts to “flatten the curve" by encouraging individuals to stay at home and maintain social distance. Since then, many individual U.S. counties and entire states have implemented stay-at-home mandates in order to reduce the speed of contagion and delay or ultimately reduce the influx of patients seeking medical treatment for COVID-19 symptoms. This study uses variation in statewide adoption of stay-at-home mandates and observed reductions in activity away from home, measured by changes in average distance traveled per day, to investigate the linkage between reduced travel and COVID-19 health outcomes. We use data on changes in mobility patterns across the U.S. since the onset of COVID-19 to discuss evidence of overall reductions in daily travel; characterize the direct impact of stay-at-home mandates on daily travel; and link travel reductions to health outcomes. We find that once mandates go into effect, residents of states with mandates reduced average distances traveled by an additional 8.1 percentage points in comparison to non-mandate states – a decline of 77% relative to the mean change during the sample period. On the day a mandate is implemented, we observe a reduction in activity levels 50% greater in magnitude than the average change. We find evidence that the observed reductions in travel ultimately improve health outcomes, as reductions in distance traveled in the three weeks prior to implementation of statewide stay-at-home are associated with 1.78 fewer daily hospitalizations and 0.22 fewer daily deaths per million due to COVID-19. Our findings provide evidence that states’ stay-at-home ordinances are having the intended effect of reducing travel, will ultimately mitigate some of the negative health consequences of COVID-19, and reflect an important policy tool in the fight against the pandemic.