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These plots show the ratio (R) of new infections from one day to the next. This is a common metric used to determine whether something is growing exponentially (R > 1), decaying exponentially (R < 1), or growing linearly (R = 1) from day to day. You can think of this as an interest rate. If you’re getting 10% interest (I wish) per year then R = 1.1, and you will double your money in 7.3 years. For example, if R = 1.2 for a day then the infections that day were 20% more than the previous day. If R = 1.2 over a number of days then whatever is being measured is doubling every 3.8 days. If R = 1.1 then doubling takes 7.3 days, and if R = 1.05 then doubling takes about two weeks. If R = 1 then the new infections for that day equaled the new infections for the previous day. I used a two-week moving average for the deaths for a given day to smooth out the noise in reporting.