The difference between inflow and outflow of migrants across years in Nepal.
Who do you think will have this data?
https://en.wikipedia.org/wiki/List_of_countries_by_net_migration_rate This needs to be verified.
International Organisation of Migration, ILO, or Pew Research Centre
What are you intending to do with the data?
I am trying to figure out the migration rates in Nepal, especially considering the hype around the Migrant Workers from Nepal and analyse its seriousness.