The 'Active cases' for each day are calculated as the 'Positive cases identified' minus 'Recoveries' minus 'Deaths' as obtained from www.sacoronavirus.co.za.
The reasoning behind this metric is to look at the burden on health services, rather than at the absolute infection growth or the death toll. The chart illustrates the extent to which the curve for each province has been flattened in order to ease this burden. The time scale starts at the day of the first case for each province of South Africa.
Using the 7-day rolling average we can smooth the data and show how new cases compare between provinces, normalised for each day.