Before revision:  We then attribute a nominal value to the intervention from the difference between true evolution and simulated counterfactual , for example, in terms of reducing the number of cases or accelerating the timecourse towards a milestone. As an example, we show that the recommendation to use facemasks for all activities would result in a putative total of 71000 (95\% CI 64000 to 78000) fewer official cases in New York State  .
After revision:  We then attribute a nominal value to the intervention from the difference between true evolution and simulated counterfactual . We show that the recommendation to use facemasks for all activities would result in a putative total of 71000 (95\% CI 64000 to 78000) fewer official cases in New York State .