Why was Lincoln’s plan for Reconstruction called the "Ten Percent Plan”?

He proposed a 10% tax on Southern crops to pay for the Union’s war debt.
He proposed taking 10% of Southern farmland and giving it to formerly enslaved people.
It would take 10% of voters in a state to meet his requirements before the state could rejoin the Union.
It would take 10% of the Southern population to work for the federal government to rebuild Southern industry.