Something like half of people don’t understand how marginal income tax rates work, but many of them have all kinds of strong opinions about federal tax policy. This is probably the single most important concept to understand about income taxes, isn’t complicated, and is something they deal with every year. Still, you’ll frequently hear them worry aloud about “moving into another tax bracket” as if it will apply to all their income.
We may expect other kinds of “basic” knowledge not to be much more widely-known than this. It’s easy to turn up similar results on fundamental civics and history. Stuff like “are Puerto Ricans US citizens?” you get a similar 30-35ish% who give the wrong answer and 15ish% “I don’t know”, pretty close to rates on questions about marginal tax rates.
We may expect other kinds of “basic” knowledge not to be much more widely-known than this. It’s easy to turn up similar results on fundamental civics and history. Stuff like “are Puerto Ricans US citizens?” you get a similar 30-35ish% who give the wrong answer and 15ish% “I don’t know”, pretty close to rates on questions about marginal tax rates.