The R number is the number of people (on average) each infected person infects. Anything over 1 means the disease soars away again. As an example Boris Johnson's personal R number is probably more than four. Hancock, Whitty, Cummings, Carrie as a quick list. He's a disaster. Apparently the R number is below 1. That's good. Some politicians, when pressed, have even tried to be more exact: 0.6-0.9 ? But (of course ?) it's higher in care homes - higher than 1 then? We currently have a daily count of five or six thousand new cases a day (reported, based on tests) then there's all the other people who've had it, stayed at home, had it, didn't know, etc. not in those figures. So could it be ten thousand new cases a day then ? twenty thousand ? Who knows ? So how the hell can anyone tell what the R number is ?