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The source is an NBER research group. https://en.wikipedia.org/wiki/National_Bureau_of_Economic_Research https://en.wikipedia.org/wiki/National_Bureau_of_Econo

by 542458 10y ago

The source is an NBER research group. https://en.wikipedia.org/wiki/National_Bureau_of_Economic_Research https://en.wikipedia.org/wiki/National_Bureau_of_Economic_Re... They're pretty well-known and trusted.