Linear regression analysis of CFR* crudetimecorrected(70+) , CFR* crudetimecorrected(70+)A , and CFR* crudetimecorrected(0 − 69) versus percent of cases 70 years old and above (p(70+)).

A shows a plot of CFR* crudetimecorrected(70+) (blue) and CFR crudetimecorrected(0 − 69) (green) for each country versus the percent of cases 70 years old and above (p(70+)). It is seen that for all countries the CFR crudetimecorrected(70) term explains the large majority of CFR crudetimecorrected (81% +/- 8%). The majority of the variance in CFR crudetimecorrected(70) is explained by cases 70 years old and above (R 2 = 0.82). B shows a plot of CFR crudetimecorrected(70+A) (blue) for each country. The value of cCFR 70+A for each country was calculated by adjusting the fraction of cases in the 70 and over group who are 80 years old and above to be 40% (p(80+)/p(70+) = 0.40), which is the mean of the countries examined ( Table 3 ). The higher fraction of the variance explained by age for CFR crudetimecorrected(70+A) (R 2 = 0.89) indicates that the percentage of the population 80 years and older are an important factor in determining the average population value of CFR crude .