571
Well, this is quite upsetting to read.
(lemmy.nz)
More (not so) fun facts:
54% of American adults read below a 6th grade level.
21% read below a 5th grade level, which is considered functionally illiterate.
High immigration numbers don't fully explain it either, as first gen immigrants only make up about 1/3 of those with low literacy.
People don't often get into tech to be writers. Also, though, I've found that paraphrased tech manuals usually leave out the most important bits of information whenever I have to use one.