The data for these graphs show can be found
here.
The numbers are the same as shown
here,
and
here.
They are occasionally revised when national authorities revise their estimates for dates in the past.For any given day the number of deaths in that day is estimates as the simple average of the number that occurred the day before and the day after. This number is then used to create a three day average centred around the day labelled. The change is the average daily change from the day before that to the day after. Conventional graphs tend to show the cumulative number of deaths attributed to the virus which, of course, always rise but will all – eventually – plateau. A cumulative total can never fall. Other published graphs have shown the number of deaths reported each day for various countries. These are more useful, but the reader is still left trying to discern the extent to which the rise from one day to the next is larger or slower. The graphs here different, most importantly by uses smoothed data.