Is Fox news unironically the best place to learn about your new favorite social dem?
It's about 20%, according to Ricardian Theorems.
You can have 80% of the population unemployed given the 20% are elite workers using automation and nearly perfect/efficient automated systems (i.e: Not farming by hand trowel, but one person controlling 10 combines/tractors simultaneously like they're playing Factorio or Farming Simulator)