Figure 1

Changes of (a) \({H}_{England, t}\) and (b) daily new COVID-19 cases in England between March 1st 2020 to May 24th 2021. For each day, the national \({H}_{England, t}\) is aggregated from the \({H}_{l, t}\) of each local authority. Accounting for the day of week effect, \({H}_{England, t}\) is also illustrated with the rolling 7-day average. New COVID-19 cases are the number of cases by specimen date. Time periods or time points where indoor mixing rules were changed were marked according.