So if I hand seven people from my state a sheet of paper that simply says, "If you ask me for money right now I will give it to you," six of them will get it and one will not.
Honest to God, I can tell you specific colonies in colonial New England that had better "level 1" literacy than the contemporary USA. Those are the same colonies that established public schools because they believed Satan was tricking them into Catholicism.
15% of adults in my state can't retrieve a single piece of information from a basic document written in simple vocabulary.
We have had public schools in this state for 159 years.