Dear all,

I'm trying to conduct a unit root test to my variables using the following code:

Code:
xtunitroot llc [variable], trend
For one of my variables it keeps returning me an "no observations" error. I've learned that this error can occur when the variables have gaps in the data, but this error is happening in a variable that has no gaps. When I summarize the variables, i get the exact same number of observations for each.

For more information I can say that variables are stored as "double type", witch I think it means that are correctly stored as numeric instead of strings. I also tried to do the same test using variables as logarithms, but the same error for the same variable keeps happening. In logarithms variables change from double to float.

Also, my data is a panel data, and for each cross (country) the value is the same, but differs from cross to cross.

Can anyone help me solving this?

I thank you all in advance.