I have the Syntax of did_imputation is as below
Array

I am wondering how to create the variable Ei.
In my case, the unique unit id is "TYPE2"
For example, I have three countries in my sample, US implement is 1995, UK implement in 1997, and Jordan never treat.
So, I think of

gen ei=1995 if GEOGN2=="US"
gen ei=1997 if GEOGN2=="UK"
gen ei=. if GEOGN2=="Jordan"
Is it correct?