Genesis 47:26

And Joseph made it a law over the land of Egypt unto this day that Pharaoh should have the fifth part, twenty percent of the income going into the royal treasury as revenue; except the land of the priests only, which became not Pharaoh's. It was a great blessing for Egypt that a man was ruler in those days who combined a high degree of wisdom with the fear of God, a combination for which any country has reasons to be thankful.