Hello everyone,

I want to create the Herfindahl-Hirschman Index for my data. I have quartlery data for different banks. I want to have the HHI for market share.

I tried the command

hhi marketshare, by(bank_id, date) however it only gives me 1 for every observation. Leaving out the date gives me results, however I want the date included.
(same with the hhi5 command). When I try the entropyetc command it says matsize too small (even after I increased the matsize)

Does anyone have a suggestion?

Thank you in advance