Before revision: Covid-19 is a large shock to the economic system and just a few months of data changed the mean of many time series in significant ways . But while Covid-19 has economic consequences, it is not an economic shock. This creates a problem for the \covid estimation of economic factors from the data.
After revision: Covid-19 is a large shock to the economic system and just a few months changed the \covid estimation of economic factors from the data.