Hey STATA community,

I currently do a project and now I am stuck in the data analysis. Therefore, I need your help AND sorry for opening a new thread with these basic questions. I just want to understand to STATA command once that I can apply it in the future without major questions..

I have firm-level data over multiple years. The literature I am following uses sector and year dummies, pseudo fixed effects and clustered standard errors on industry-level. Now I wonder, how I can fit all that into one model.

I set my panel using:
xtset companynum DataYearFiscal, yearly
Whereas companynum is the company identifier and DataYearFiscal is the year.

So far, I managed to build the following model:
xtreg DepVar IndVar1 IndVar2 ... IndVarn i.DataYearFiscal i.companynum, vce (cluster Industry)
I have some questions to better understand the command.
Does is fit the above-mentioned requirements?
i.DataYearFiscal and i.companynum are dummies, aren't they? Are they used to cover time-variant effects and firm-variant effects respectively?
vce (cluster Industry) says clustered standard errors on industry-level to account for differences between industries (e.g. manufacturing vs retail). What happens if I exclude it?
If I include fe, i.companynum is ommited because of collinearity.

The above-mentioned model, however, has an R-Square between = 1.0000. That seems odd to me. Why is this so? Where did I take the wrong exit?

Thank you very much!
Tobi