The corona reproduction number R is a function of …?

The number of corona infections can roughly be modeled as N ~ R^t, where t is time1 and R is the reproduction number. The reproduction number R is the average number of new infections caused by one person infected with Covid-19.

If R > 1, the number of patients grows exponentially. If R < 1, the epidemic fizzles out.

How do people get infected? Obviously, they have to come into contact with the virus.

R is high when people are close together, indoors, and talking/singing/shouting. That explains why most infections occur at care facilities, slaughterhouses, prisons and at home2. There also seems to be a climatological effect. Sunlight, heat and humidity are correlated with a lower R. Genetic and (tuberculosis) vaccination differences between populations have been suggested to play a role.

Johannes Borgen (@jeuasommenulle) has estimated R for different countries3. You can find his methodology here.

As expected, lockdowns reduce R to below 1.

According to this map, the pandemic is still growing in Latin America, Africa and South Asia.

Life insurers are the real yieldbugs

Pseudonymous banking expert Johannes Borgen recently discussed the impact of low interest rates on European life insurers. Because insurers discount the value of their liabilities, low rates are a huge problem.

But as Johannes Borgen points out, the regulator lets insurers use a hypothetical long term rate that “is a f**** joke. IT IS NOT EVEN REMOTELY LOOKING LIKE REAL WORLD INTEREST RATES ; which mean that all insurer liabilities are grossly undervalued.”


You can read his thread here:

By the way, yieldbug is a term used by Bloomberg journalist Joe Weisenthal to troll people who believe they deserve to receive interest on their risk free investment.