What does Genesis 47:24 mean?

When harvest comes, you’ll give one-fifth of your crops to Pharaoh. The other four-fifths you can keep for yourselves, your families, and for planting next year. Genesis 47:24 - Modern Text Bible

(Joseph sets up a system where the people pay a 20% tax on their harvest to Pharaoh, but they get to keep the rest. It’s a way to make sure Pharaoh benefits, but the people can still survive and rebuild.)