This should help:
List of US states by Educational Attainment.
I would note that this subject has been trotted out previously across the world. One of the problems is "talking past each other" as to what "educational attainment", or reading skills, actually is. What is being meant, what is being measured, as "basic reading skills".
Some people mean it to be basic reading and writing skills, i.e. just enough ability to read a utility bill or a speeding ticket. Or at least recognise their own name and address on a letter. This is a rudimentary level of reading.
Others mean the ability to read and comprehend basic stories in newspapers and books, to write a letter, and a cheque (US only). at a junior school level. This is a basic level of reading.
And others again mean the ability to locate, read and comprehend many complex documents with wide-ranging vocabularies such as university research papers, jurisprudence legal documents, and government policy and legislation. This is an advanced level of reading.
None of these things is much like the others.
Similarly for mathematics abilities: basic arithmetic, versus basic algebra and trigonometry, versus calculus and on up.
Define your measures, i.e. define your expectations.