Minimum number of observations required in panel data regression

[Peter Sutton]

Hello all,

I am working with stata and running panel data regressions. I want to write on the influence of greenwashing on financial performance for 50 countries. However, what is the minimum number of observations I should use for this analysis to be valid?

Best regards,
Peter

[Carlo Lazzaro]

Peter:
welcome to this forum.
At least two observations per panel (two waves of data per country) sounds as a wise requirement.