From the Gallup Poll:
Four in 10 Americans, slightly fewer today than in years past, believe God created humans in their present form about 10,000 years ago.
They’ve been asking the question since 1982 and it’s been pretty steady at 45%, so in some sense this is good news! (I’m saying this under the completely unsupported belief that it’s better for people to believe truths than falsehoods.)
One way to think of this is that, for the overwhelming majority of people, a personal belief in young-earth creationism (or whatever you want to call it) is costless. Or, to put it another way, the discomfort involved in holding a belief that contradicts everything you were taught in school is greater than the discomfort involved in holding a belief that seems to contradict your religious values (keeping in mind that, even among those who report attending church seldom or never, a quarter of these people agree that “God created humans in their present form about 10,000 years ago”).
Some of this is political (see further discussion here), but lots of Democrats and independents believe that 10,000 years thing too, so, just as with impressions about inflation and unemployment, it looks like there’s just a high general level of ignorance on the matter.
P.S. Of the remaining 60% of survey respondents, 38% agreed with the statement, “Human beings have developed over millions of years from less advanced forms of life, but God guided the process,” 16% believed “Human beings have developed over millions of years from less advanced forms of life, but God had no part in this process,” and I suppose the remaining 6% declined to state an opinion. I don’t really have any comment on the “God guided the process” bit, as it seems vague enough to mean just about anything. (I’m not saying it’s a bad survey question, just that it could pretty much mean whatever you want it to mean.) Also, I suspect that many biologists would object to the “less advanced forms of life” bit, but I think I know what people think when this question is asked.
P.P.S. Yes, I know that people are ignorant on many many topics, not just evolution, inflation, and unemployment. Feel free to leave your favorites in the comments.
P.P.P.S. The question appears to be so that you have to either believe in evolution, or believe that humans are 10,000 years old. You can’t, for example, state that humans didn’t evolve but were created 50,000 years ago.