GRE Chemistry score

[EthyleneDiAmine]

I am confusing about the way they score the GRE chemistry subject. In the practice book it stated that: "GRE Chemistry Test total scores are reported on a 200 to 990 score scale in ten-point increments"

But down in scoring the practice test section; it refers to a table called Total score conversion table on page 52. To find the Scaled Total score that corresponds to the Raw Total score. in this table the minimum score is 430, and the raw scores and their corresponds scores are not the same on the previous practice tests (older versions for the few past years).

 

Any idea what is wrong here? is 430 the minimum score? Seriously?