Depending on the shift between the curves of deaths/cases we defined termporal lethality rate.
Depending on the temporal shift between cases and deaths identified (one week or >1 weeks) the Weekly Lethality Rate (WLR) was defined as the ratio between the average number of deaths of a certain week (Wi) and the average number of cases of one or more weeks before (Wi-1, Wi-2 etc).
where x represents the shift identified in terms of number of weeks.