It's a good question, I do know the immigration numbers (ex-pats) are way for a couple of years now for obvious reasons. Bukele is now even witholding business taxation on foreign residents starting up businesses in ES.

But yeah the emigration numbers have to be down, maybe they're mostly bad hombres escaping imprisonment. In theory the economic up-turn and ongoing investments in the country should be encouraging to regular middle and lower class citizens to stick around, instead of illegally look for a fabled better life.