This is the UK. The number is rate of growth, not number of cases Its similar to Rt but its much easier to calculate. To get Rt, you need to estimate how many

This is the UK. The number is rate of growth, not number of cases Its similar to Rt but its much easier to calculate. To get Rt, you need to estimate how many people are infected on average by one person at any point in time. This is usually done by simulating the process in various ways. To get the daily rate of growth on the other hand, all you need to do is look at the actual numbers. Assuming you had 110 cases today and 100 cases yesterday, the current rate of growth is 10%. Since the rate calculated this way will be a bit erratic, I use some averaging and exponential smoothing to get the general trend. The code to generate these graphs is available here: https://colab.research.google.com/drive/1QDZgdGkOzs6dP74-iEDTDee2B02Admdt https://colab.research.google.com/drive/1QDZgdGkOzs6dP74-iED... - it uses the UK coronavirus API and google mobility trends reports directly from their respective URLs, so it should be easy to make a copy of the notebook, review/modify it and re-run it. Why is the ratio of positive cases to hospitalizations different? I'd say this is mostly due to testing capacities being very different between now and March. In March in the UK for example it was impossible to get a test unless things are so bad that you need to get hospitalized. This is very different from now where anyone with symptoms (or just saying they have symptoms) can get tested. Based on the graph, another reason for the different ratio between cases and deaths seems to be the period July to mid August. This was a period where the growth rate of cases didn't match the growth rate of hospitalizations and deaths at all. This likely means that parts of the population that wasn't that succeptable to severe outcomes were getting infected (which makes sense given that bars were opened up again at the beginning of July - although that is speculation)